Solutions for Week-9 exercice
 

1- Na5Cr3F14

We will start from the last refinement by SHELXL97, done Week-6 :
 

   "Na5Cr3F14" ???  P21/n                                                   

ATOM           x         y         z          sof         U11      

Cr1         0.00000   0.00000   0.00000     0.50000     0.00975
  0.00000   0.00000   0.00000   0.00000     0.00000     0.00258

Cr2         0.00000  -0.50000   0.00000     0.50000     0.01708
  0.00000   0.00000   0.00000   0.00000     0.00000     0.00270

Cr3         0.00000   0.00000   0.50000     0.50000     0.01520
  0.00000   0.00000   0.00000   0.00000     0.00000     0.00266

Na1         0.25203  -0.29049   0.23079     1.00000     0.01711
  0.01553   0.00058   0.00149   0.00112     0.00000     0.00272

Na2         0.24149  -0.23213   0.71832     1.00000     0.02599
  0.01584   0.00068   0.00137   0.00159     0.00000     0.00304

Na3         0.00000  -0.50000   0.50000     0.50000     0.04671
  0.00000   0.00000   0.00000   0.00000     0.00000     0.00771

F1          0.11133  -0.48292  -0.19121     1.00000     0.02815
  0.02857   0.00164   0.00187   0.00242     0.00000     0.00431

F2          0.13946   0.17073   0.52688     1.00000     0.02398
  0.02376   0.00127   0.00193   0.00185     0.00000     0.00346

F3         -0.11215   0.20536   0.53896     1.00000     0.02629
  0.02344   0.00113   0.00190   0.00198     0.00000     0.00363

F4          0.03585  -0.24438   0.06251     1.00000     0.02297
  0.02015   0.00108   0.00163   0.00181     0.00000     0.00355

F5         -0.12985  -0.44000  -0.17702     1.00000     0.01530
  0.01919   0.00091   0.00165   0.00146     0.00000     0.00342

F6          0.17163   0.03878  -0.00998     1.00000     0.02986
  0.02805   0.00144   0.00211   0.00229     0.00000     0.00366

F7          0.00411   0.07027   0.24910     1.00000     0.01968
  0.02050   0.00098   0.00180   0.00165     0.00000     0.00372



Final Structure Factor Calculation for    "Na5Cr3F14" ???  P21/n                                                   

Total number of l.s. parameters =    41     Maximum vector length =  511      Memory required =   2708 /   21973

R1 =  0.2220 for   1091 Fo > 4sig(Fo)  and  0.2267 for all   1127 data
wR2 =  0.7684,  GooF = S =  11.182,  Restrained GooF =   11.182  for all data

From these coordinates, the FULLPROF file is built (na5.pcr) :
 
COMM   Na5Cr3F14  ??                                                      
! Files => DAT-file: na5,  PCR-file: na5
!Job Npr Nph Nba Nex Nsc Nor Dum Iwg Ilo Ias Res Ste Nre Cry Uni Cor
   0   5   1  14   2   0   1   1   0   0   1   0   0   0   0   0   0
!
!Ipr Ppl Ioc Mat Pcr Ls1 Ls2 Ls3 Syo Prf Ins Rpa Sym Hkl Fou Sho Ana
   0   0   1   0   1   0   0   0   1   1   0   1   0   1   2   0   0
!
! lambda1 Lambda2    Ratio   Bkpos    Wdt    Cthm     muR   AsyLim   Rpolarz
 1.540560 1.544390  0.5000 90.0000 15.0000  0.7995  0.0000   80.00    0.0000
!
!NCY Eps R_at R_an R_pr R_gl     Thmin       Step       Thmax    PSD    Sent0
 10 0.01 0.60 0.60 0.60 0.80     10.0000     0.0100   150.0000  0.000  0.000
!
!  2Theta/TOF   Background
       10.000      447.800
       11.850      418.910
       13.250      394.140
       19.040      352.870
       22.050      334.300
       26.690      315.730
       32.480      299.220
       47.550      288.900
       61.230      274.460
       73.510      253.820
       90.430      222.870
      111.990      204.290
      140.260      208.420
      150.000      214.610
! 
! Excluded regions (LowT  HighT)
        1.00       10.00
      150.00      170.00
! 
!
       1    !Number of refined parameters
!
!  Zero    Code    Sycos    Code   Sysin    Code  Lambda     Code MORE
  0.0911  141.00  0.0000    0.00  0.0063  121.00 0.000000    0.00   0
!-------------------------------------------------------------------------------
!  Data for PHASE number:   1  ==> Current R_Bragg:    33.18
!-------------------------------------------------------------------------------
   Na5Cr3F14 ??                                                       
!
!Nat Dis Mom Pr1 Pr2 Pr3 Jbt Irf Isy Str Furth     ATZ   Nvk Npr More
  13   0   0 1.0 0.0 0.0   0   0   0   0   0        0.00   0   5   0
!
P 21/N                   <--Space group symbol
!Atom Typ       X        Y        Z     Biso      Occ     In Fin N_t  /Codes
CR1  CR+3    0.00000  0.00000  0.00000  0.50000  0.50000   0   0   0
                0.00     0.00     0.00     0.00     0.00
CR2  CR+3    0.00000 -0.50000  0.00000  0.50000  0.50000   0   0   0
                0.00     0.00     0.00     0.00     0.00
CR3  CR+3    0.00000  0.00000  0.50000  0.50000  0.50000   0   0   0
                0.00     0.00     0.00     0.00     0.00
NA1  NA+1    0.25203 -0.29049  0.23079  2.00000  1.00000   0   0   0
                0.00     0.00     0.00     0.00     0.00
NA2  NA+1    0.24149 -0.23213  0.71832  2.00000  1.00000   0   0   0
                0.00     0.00     0.00     0.00     0.00
NA3  NA+1    0.00000 -0.50000  0.50000  0.50000  0.50000   0   0   0
                0.00     0.00     0.00     0.00     0.00
F1   F-1     0.11133 -0.48292 -0.19121  1.20000  1.00000   0   0   0
                0.00     0.00     0.00     0.00     0.00
F2   F-1     0.13946  0.17073  0.52688  1.20000  1.00000   0   0   0
                0.00     0.00     0.00     0.00     0.00
F3   F-1    -0.11215  0.20536  0.53896  1.20000  1.00000   0   0   0
                0.00     0.00     0.00     0.00     0.00
F4   F-1     0.03585 -0.24438  0.06251  1.20000  1.00000   0   0   0
                0.00     0.00     0.00     0.00     0.00
F5   F-1    -0.12985 -0.44000 -0.17702  1.20000  1.00000   0   0   0
                0.00     0.00     0.00     0.00     0.00
F6   F-1     0.17163  0.03878 -0.00998  1.20000  1.00000   0   0   0
                0.00     0.00     0.00     0.00     0.00
F7   F-1     0.00411  0.07027  0.24910  1.20000  1.00000   0   0   0
                0.00     0.00     0.00     0.00     0.00
!  Scale       Shape1      Bov     Str1     Str2     Str3    Strain-Model
 0.10000E-01   0.4782   0.0000   0.0000   0.0000   0.0000       0
    11.00000    21.00     0.00     0.00     0.00     0.00
!      U        V         W          X         Y       GauSiz   LorSiz Size-Model
   0.00159   0.00198   0.00173   0.00310   0.00000   0.00000   0.00000   0
     51.00     41.00     31.00    131.00      0.00      0.00      0.00
!     a          b         c        alpha      beta       gamma
  10.509497   7.225223   7.271324  90.000000  90.674828  90.000000
   81.00000   91.00000  101.00000    0.00000  111.00000    0.00000
!  Pref1  Pref2   Asy1    Asy2    Asy3     Asy4
 1.00000 0.00000 0.02956 0.00088 0.00000 0.00000
    0.00    0.00   61.00   71.00    0.00    0.00
Note that all the parameters refined at the "|Fobs|" extraction stage are kept fixed. Only a scale factor is refined at this stage. The fit is already quite good :
 
 ==> RELIABILITY FACTORS WITH ALL NON-EXCLUDED POINTS:

 => Cycle: 10 => MaxCycle: 10
 => N-P+C: 13999
 => Rp: 8.05     Rwp: 10.7     Rexp:    2.81 Chi2:  14.5      L.S. refinement
 => Conventional Rietveld R-factors ==>
 => Rp: 10.1     Rwp: 12.7     Rexp:    3.35 Chi2:  14.5    
 => Deviance: 0.195E+06     Dev*  :  13.94    
 => DW-Stat.:    0.1695     DW-exp:     1.9478
 => N-sigma of the GoF: 1126.128

 ==> RELIABILITY FACTORS FOR POINTS WITH BRAGG CONTRIBUTIONS:

 => N-P+C: 13291
 => Rp: 8.10     Rwp: 10.8     Rexp:    2.76 Chi2:  15.2      L.S. refinement
 => Conventional Rietveld R-factors ==>
 => Rp: 10.0     Rwp: 12.7     Rexp:    3.27 Chi2:  15.2    
 => Deviance: 0.194E+06     Dev*  :  14.61    
 => DW-Stat.:    0.1703     DW-exp:     1.9464
 => N-sigma of the GoF:     1154.139
 => Phase:  1
 => Bragg R-factor:  8.83       Vol:  552.098( 0.000)  Fract(%):    0.00( 0.00)
 => Rf-factor= 6.69             ATZ:    0.000          Brindley:  1.0000


 

Now, and because the fit is already that good, we may expect to refine all the atomic coordinates as well as the isotropic thermal parameters (in a first step, grouping same atom-type with one thermal parameter). But the fit will not always be that good at this stage if the structure model is not complete. In such a case, it is recommended to fix the profile parameters (U, V, W, cell parameters, zeropoint, etc) that were obtained at the structure factors extraction stage, up to obtain a structure model which lead tp reliability factors sufficiently small (<20%), otherwise, those profile parameters may prove to be unstable and the fit may diverge.

In this especially straightforward case, let us refine all parameters together (44 parameters already) :
 

COMM   Na5Cr3F14  ??                                                      
! Files => DAT-file: na5,  PCR-file: na5
!Job Npr Nph Nba Nex Nsc Nor Dum Iwg Ilo Ias Res Ste Nre Cry Uni Cor
   0   5   1  14   2   0   1   1   0   0   1   0   0   0   0   0   0
!
!Ipr Ppl Ioc Mat Pcr Ls1 Ls2 Ls3 Syo Prf Ins Rpa Sym Hkl Fou Sho Ana
   0   0   1   0   1   0   0   0   1   1   0   1   0   1   2   0   0
!
! lambda1 Lambda2    Ratio   Bkpos    Wdt    Cthm     muR   AsyLim   Rpolarz
 1.540560 1.544390  0.5000 90.0000 15.0000  0.7995  0.0000   80.00    0.0000
!
!NCY Eps R_at R_an R_pr R_gl     Thmin       Step       Thmax    PSD    Sent0
 10 0.01 0.60 0.60 0.60 0.80     10.0000     0.0100   150.0000  0.000  0.000
!
!  2Theta/TOF   Background
       10.000      447.800
       11.850      418.910
       13.250      394.140
       19.040      352.870
       22.050      334.300
       26.690      315.730
       32.480      299.220
       47.550      288.900
       61.230      274.460
       73.510      253.820
       90.430      222.870
      111.990      204.290
      140.260      208.420
      150.000      214.610
! 
! Excluded regions (LowT  HighT)
        1.00       10.00
      150.00      170.00
! 
!
      44    !Number of refined parameters
!
!  Zero    Code    Sycos    Code   Sysin    Code  Lambda     Code MORE
  0.0911  141.00  0.0000    0.00  0.0063  121.00 0.000000    0.00   0
!-------------------------------------------------------------------------------
!  Data for PHASE number:   1  ==> Current R_Bragg:     8.83
!-------------------------------------------------------------------------------
   Na5Cr3F14 ??                                                       
!
!Nat Dis Mom Pr1 Pr2 Pr3 Jbt Irf Isy Str Furth     ATZ   Nvk Npr More
  13   0   0 1.0 0.0 0.0   0   0   0   0   0        0.00   0   5   0
!
P 21/N                   <--Space group symbol
!Atom Typ       X        Y        Z     Biso      Occ     In Fin N_t  /Codes
CR1  CR+3    0.00000  0.00000  0.00000  0.50000  0.50000   0   0   0
                0.00     0.00     0.00   421.00     0.00
CR2  CR+3    0.00000 -0.50000  0.00000  0.50000  0.50000   0   0   0
                0.00     0.00     0.00   421.00     0.00
CR3  CR+3    0.00000  0.00000  0.50000  0.50000  0.50000   0   0   0
                0.00     0.00     0.00   421.00     0.00
NA1  NA+1    0.25203 -0.29049  0.23079  2.00000  1.00000   0   0   0
              151.00   161.00   171.00   431.00     0.00
NA2  NA+1    0.24149 -0.23213  0.71832  2.00000  1.00000   0   0   0
              181.00   191.00   201.00   431.00     0.00
NA3  NA+1    0.00000 -0.50000  0.50000  0.50000  0.50000   0   0   0
                0.00     0.00     0.00   431.00     0.00
F1   F-1     0.11133 -0.48292 -0.19121  1.20000  1.00000   0   0   0
              211.00   221.00   231.00   441.00     0.00
F2   F-1     0.13946  0.17073  0.52688  1.20000  1.00000   0   0   0
              241.00   251.00   261.00   441.00     0.00
F3   F-1    -0.11215  0.20536  0.53896  1.20000  1.00000   0   0   0
              271.00   281.00   291.00   441.00     0.00
F4   F-1     0.03585 -0.24438  0.06251  1.20000  1.00000   0   0   0
              301.00   311.00   321.00   441.00     0.00
F5   F-1    -0.12985 -0.44000 -0.17702  1.20000  1.00000   0   0   0
              331.00   341.00   351.00   441.00     0.00
F6   F-1     0.17163  0.03878 -0.00998  1.20000  1.00000   0   0   0
              361.00   371.00   381.00   441.00     0.00
F7   F-1     0.00411  0.07027  0.24910  1.20000  1.00000   0   0   0
              391.00   401.00   411.00   441.00     0.00
!  Scale       Shape1      Bov     Str1     Str2     Str3    Strain-Model
 0.52489E-02   0.4782   0.0000   0.0000   0.0000   0.0000       0
    11.00000    21.00     0.00     0.00     0.00     0.00
!      U        V         W          X         Y       GauSiz   LorSiz Size-Model
   0.00159   0.00198   0.00173   0.00310   0.00000   0.00000   0.00000   0
     51.00     41.00     31.00    131.00      0.00      0.00      0.00
!     a          b         c        alpha      beta       gamma
  10.509497   7.225223   7.271324  90.000000  90.674843  90.000000
   81.00000   91.00000  101.00000    0.00000  111.00000    0.00000
!  Pref1  Pref2   Asy1    Asy2    Asy3     Asy4
 1.00000 0.00000 0.02956 0.00088 0.00000 0.00000
    0.00    0.00   61.00   71.00    0.00    0.00
The result is quite satisfying (.sum file) :
 
 ==> ATOM PARAMETERS:

  Name    x     sx       y     sy       z      sz      B   sB  occ.  socc.

 CR1   0.00000(   0)  0.00000(   0)  0.00000(   0)  0.904(  4)  0.500(  0)
 CR2   0.00000(   0) -0.50000(   0)  0.00000(   0)  0.904(  4)  0.500(  0)
 CR3   0.00000(   0)  0.00000(   0)  0.50000(   0)  0.904(  4)  0.500(  0)
 NA1   0.24828(  13) -0.29496(  14)  0.23245(  17)  2.393( 14)  1.000(  0)
 NA2   0.24434(  12) -0.23124(  15)  0.72045(  16)  2.393( 14)  1.000(  0)
 NA3   0.00000(   0) -0.50000(   0)  0.50000(   0)  0.893( 14)  0.500(  0)
 F1    0.11575(  12) -0.48895(  19) -0.19171(  18)  1.661( 11)  1.000(  0)
 F2    0.13435(  13)  0.16495(  18)  0.53026(  19)  1.661( 11)  1.000(  0)
 F3   -0.10988(  12)  0.20071(  18)  0.54342(  19)  1.661( 11)  1.000(  0)
 F4    0.03466(  13) -0.24671(  17)  0.06751(  19)  1.661( 11)  1.000(  0)
 F5   -0.12630(  13) -0.44057(  19) -0.17723(  18)  1.661( 11)  1.000(  0)
 F6    0.17573(  11)  0.03950(  18) -0.00907(  18)  1.661( 11)  1.000(  0)
 F7    0.00028(  14)  0.07217(  17)  0.24652(  20)  1.661( 11)  1.000(  0)

 ==> PROFILE PARAMETERS:

 => Cell parameters      :
                             10.50958   0.00002
                              7.22529   0.00001
                              7.27133   0.00001
                             90.00000   0.00000
                             90.67539   0.00011
                             90.00000   0.00000
 
 => overall scale factor :    0.005705233   0.000006265
 => Eta(p-v) or m(p-vii) :    0.43728   0.00400
 => Overall tem. factor  :    0.00000   0.00000
 => Halfwidth parameters :    0.00241   0.00006
                              0.00104   0.00006
                              0.00202   0.00002
 => Preferred orientation:    1.00000   0.00000
                              0.00000   0.00000
 => Asymmetry parameters :    0.06095   0.00201
                              0.00057   0.00032
                              0.00000   0.00000
                              0.00000   0.00000
 => X and y parameters   :    0.00437   0.00009
                              0.00000   0.00000
 => Strain parameters    :    0.00000   0.00000
                              0.00000   0.00000
                              0.00000   0.00000
 => Size   parameters    :    0.00000   0.00000
                              0.00000   0.00000

 ==> GLOBAL PARAMETERS:

 => Zero-point:   0.0950  0.0002
 => Cos( theta)-shift parameter :   0.0000  0.0000
 => Sin(2theta)-shift parameter :   0.0032  0.0003

 ==> RELIABILITY FACTORS WITH ALL NON-EXCLUDED POINTS:

 => Cycle: 10 => MaxCycle: 10
 => N-P+C: 13956
 => Rp: 3.78     Rwp: 5.54     Rexp:    2.81 Chi2:  3.88      L.S. refinement
 => Conventional Rietveld R-factors ==>
 => Rp: 4.74     Rwp: 6.59     Rexp:    3.35 Chi2:  3.88    
 => Deviance: 0.542E+05     Dev*  :  3.880    
 => DW-Stat.:    0.5371     DW-exp:     1.9539
 => N-sigma of the GoF:  240.708

 ==> RELIABILITY FACTORS FOR POINTS WITH BRAGG CONTRIBUTIONS:

 => N-P+C: 13270
 => Rp: 3.77     Rwp: 5.53     Rexp:    2.76 Chi2:  4.02      L.S. refinement
 => Conventional Rietveld R-factors ==>
 => Rp: 4.66     Rwp: 6.54     Rexp:    3.26 Chi2:  4.02    
 => Deviance: 0.532E+05     Dev*  :  4.011    
 => DW-Stat.:    0.5461     DW-exp:     1.9529
 => N-sigma of the GoF:      245.594
 => Phase:  1
 => Bragg R-factor:  3.58       Vol:  552.109( 0.002)  Fract(%):    0.00( 0.00)
 => Rf-factor= 3.96             ATZ:    0.000          Brindley:  1.0000
We may now try to do more. Instead of the manually estimated background, we may see if a polynomial background would not improve that fit. In such a case, the best is to put all 6 polynomial values to zero, excepted the first which can be given the value of the lowest background. Moreover, it is recommended to refine only the background values (note that if the pattern presents a limited 2-theta max value, it will not always be possible to refine all the 6 background polynomial values).

The new .pcr file becomes :
 

COMM   Na5Cr3F14  ??                                                      
! Files => DAT-file: na5,  PCR-file: na5
!Job Npr Nph Nba Nex Nsc Nor Dum Iwg Ilo Ias Res Ste Nre Cry Uni Cor
   0   5   1   0   2   0   1   1   0   0   1   0   0   0   0   0   0
!
!Ipr Ppl Ioc Mat Pcr Ls1 Ls2 Ls3 Syo Prf Ins Rpa Sym Hkl Fou Sho Ana
   0   0   1   0   1   0   0   0   1   1   0   1   0   1   2   0   0
!
! lambda1 Lambda2    Ratio   Bkpos    Wdt    Cthm     muR   AsyLim   Rpolarz
 1.540560 1.544390  0.5000 90.0000 15.0000  0.7995  0.0000   80.00    0.0000
!
!NCY Eps R_at R_an R_pr R_gl     Thmin       Step       Thmax    PSD    Sent0
 10 0.01 0.60 0.60 0.60 0.80     10.0000     0.0100   150.0000  0.000  0.000
! 
! Excluded regions (LowT  HighT)
        1.00       10.00
      150.00      170.00
! 
!
       6    !Number of refined parameters
!
!  Zero    Code    Sycos    Code   Sysin    Code  Lambda     Code MORE
  0.0950  141.00  0.0000    0.00  0.0032  121.00 0.000000    0.00   0
!   Background coefficients/codes
  150.00        0.00        0.00        0.00        0.00         0.0    
      11.000      21.000      31.000      41.000      51.000      61.000
!-------------------------------------------------------------------------------
!  Data for PHASE number:   1  ==> Current R_Bragg:     3.58
!-------------------------------------------------------------------------------
   Na5Cr3F14 ??                                                       
!
!Nat Dis Mom Pr1 Pr2 Pr3 Jbt Irf Isy Str Furth     ATZ   Nvk Npr More
  13   0   0 1.0 0.0 0.0   0   0   0   0   0        0.00   0   5   0
!
P 21/N                   <--Space group symbol
!Atom Typ       X        Y        Z     Biso      Occ     In Fin N_t  /Codes
CR1  CR+3    0.00000  0.00000  0.00000  0.90367  0.50000   0   0   0
                0.00     0.00     0.00   421.00     0.00
CR2  CR+3    0.00000 -0.50000  0.00000  0.90367  0.50000   0   0   0
                0.00     0.00     0.00   421.00     0.00
CR3  CR+3    0.00000  0.00000  0.50000  0.90367  0.50000   0   0   0
                0.00     0.00     0.00   421.00     0.00
NA1  NA+1    0.24828 -0.29496  0.23245  2.39280  1.00000   0   0   0
              151.00   161.00   171.00   431.00     0.00
NA2  NA+1    0.24434 -0.23124  0.72045  2.39280  1.00000   0   0   0
              181.00   191.00   201.00   431.00     0.00
NA3  NA+1    0.00000 -0.50000  0.50000  0.89280  0.50000   0   0   0
                0.00     0.00     0.00   431.00     0.00
F1   F-1     0.11575 -0.48895 -0.19171  1.66140  1.00000   0   0   0
              211.00   221.00   231.00   441.00     0.00
F2   F-1     0.13435  0.16495  0.53026  1.66140  1.00000   0   0   0
              241.00   251.00   261.00   441.00     0.00
F3   F-1    -0.10988  0.20071  0.54342  1.66140  1.00000   0   0   0
              271.00   281.00   291.00   441.00     0.00
F4   F-1     0.03466 -0.24671  0.06751  1.66140  1.00000   0   0   0
              301.00   311.00   321.00   441.00     0.00
F5   F-1    -0.12630 -0.44057 -0.17723  1.66140  1.00000   0   0   0
              331.00   341.00   351.00   441.00     0.00
F6   F-1     0.17573  0.03950 -0.00907  1.66140  1.00000   0   0   0
              361.00   371.00   381.00   441.00     0.00
F7   F-1     0.00028  0.07217  0.24652  1.66140  1.00000   0   0   0
              391.00   401.00   411.00   441.00     0.00
!  Scale       Shape1      Bov     Str1     Str2     Str3    Strain-Model
 0.57052E-02   0.4373   0.0000   0.0000   0.0000   0.0000       0
   451.00000   461.00     0.00     0.00     0.00     0.00
!      U        V         W          X         Y       GauSiz   LorSiz Size-Model
   0.00241   0.00104   0.00202   0.00437   0.00000   0.00000   0.00000   0
    491.00    481.00    471.00    131.00      0.00      0.00      0.00
!     a          b         c        alpha      beta       gamma
  10.509584   7.225294   7.271334  90.000000  90.675392  90.000000
   81.00000   91.00000  101.00000    0.00000  111.00000    0.00000
!  Pref1  Pref2   Asy1    Asy2    Asy3     Asy4
 1.00000 0.00000 0.06095 0.00057 0.00000 0.00000
    0.00    0.00  501.00   71.00    0.00    0.00
A first run is done with those 6 parameters only, and then, if the refinement is satisfying, the whole set of parameters are refined (now 50 parameters) :
 
 =>  No. of reflections:   2264


 ==> ATOM PARAMETERS:

  Name    x     sx       y     sy       z      sz      B   sB  occ.  socc.

 CR1   0.00000(   0)  0.00000(   0)  0.00000(   0)  0.816(  5)  0.500(  0)
 CR2   0.00000(   0) -0.50000(   0)  0.00000(   0)  0.816(  5)  0.500(  0)
 CR3   0.00000(   0)  0.00000(   0)  0.50000(   0)  0.816(  5)  0.500(  0)
 NA1   0.24815(  12) -0.29537(  13)  0.23214(  16)  2.321( 14)  1.000(  0)
 NA2   0.24418(  11) -0.23082(  14)  0.71992(  15)  2.321( 14)  1.000(  0)
 NA3   0.00000(   0) -0.50000(   0)  0.50000(   0)  0.821( 14)  0.500(  0)
 F1    0.11566(  11) -0.48872(  18) -0.19181(  16)  1.607( 11)  1.000(  0)
 F2    0.13429(  12)  0.16474(  17)  0.53039(  18)  1.607( 11)  1.000(  0)
 F3   -0.10967(  11)  0.20043(  17)  0.54343(  18)  1.607( 11)  1.000(  0)
 F4    0.03485(  12) -0.24676(  16)  0.06737(  18)  1.607( 11)  1.000(  0)
 F5   -0.12601(  12) -0.44067(  17) -0.17694(  16)  1.607( 11)  1.000(  0)
 F6    0.17565(  10)  0.03977(  16) -0.00912(  17)  1.607( 11)  1.000(  0)
 F7    0.00002(  13)  0.07200(  16)  0.24582(  19)  1.607( 11)  1.000(  0)

 ==> PROFILE PARAMETERS:

 => Cell parameters      :
                             10.50958   0.00002
                              7.22528   0.00001
                              7.27133   0.00001
                             90.00000   0.00000
                             90.67535   0.00010
                             90.00000   0.00000
 
 => overall scale factor :    0.005666310   0.000006379
 => Eta(p-v) or m(p-vii) :    0.42389   0.00380
 => Overall tem. factor  :    0.00000   0.00000
 => Halfwidth parameters :    0.00255   0.00006
                              0.00090   0.00006
                              0.00205   0.00002
 => Preferred orientation:    1.00000   0.00000
                              0.00000   0.00000
 => Asymmetry parameters :    0.06045   0.00191
                              0.00056   0.00030
                              0.00000   0.00000
                              0.00000   0.00000
 => X and y parameters   :    0.00483   0.00008
                              0.00000   0.00000
 => Strain parameters    :    0.00000   0.00000
                              0.00000   0.00000
                              0.00000   0.00000
 => Size   parameters    :    0.00000   0.00000
                              0.00000   0.00000

 ==> GLOBAL PARAMETERS:

 => Zero-point:   0.0950  0.0002
 => Background Polynomial Parameters ==>
                              203.253    0.805318    
                             -142.554     3.25243    
                              404.226     9.36827    
                              601.180     19.6487    
                             -862.140     22.7986    
                             -1367.21     33.1536    
 
 => Cos( theta)-shift parameter :   0.0000  0.0000
 => Sin(2theta)-shift parameter :   0.0032  0.0003

 ==> RELIABILITY FACTORS WITH ALL NON-EXCLUDED POINTS:

 => Cycle: 10 => MaxCycle: 10
 => N-P+C: 13950
 => Rp: 3.60     Rwp: 5.19     Rexp:    2.81 Chi2:  3.41      L.S. refinement
 => Conventional Rietveld R-factors ==>
 => Rp: 4.48     Rwp: 6.15     Rexp:    3.33 Chi2:  3.41    
 => Deviance: 0.481E+05     Dev*  :  3.448    
 => DW-Stat.:    0.6072     DW-exp:     1.9548
 => N-sigma of the GoF:  201.555

 ==> RELIABILITY FACTORS FOR POINTS WITH BRAGG CONTRIBUTIONS:

 => N-P+C: 13264
 => Rp: 3.59     Rwp: 5.18     Rexp:    2.76 Chi2:  3.53      L.S. refinement
 => Conventional Rietveld R-factors ==>
 => Rp: 4.40     Rwp: 6.09     Rexp:    3.24 Chi2:  3.53    
 => Deviance: 0.473E+05     Dev*  :  3.562    
 => DW-Stat.:    0.6182     DW-exp:     1.9538
 => N-sigma of the GoF:      205.711
 => Phase:  1
 => Bragg R-factor:  3.24       Vol:  552.108( 0.002)  Fract(%):    0.00( 0.00)
 => Rf-factor= 3.11             ATZ:    0.000          Brindley:  1.0000


We can now try to refine all thermal parameters independently (60 parameters) :
 

COMM   Na5Cr3F14  ??                                                      
! Files => DAT-file: na5,  PCR-file: na5
!Job Npr Nph Nba Nex Nsc Nor Dum Iwg Ilo Ias Res Ste Nre Cry Uni Cor
   0   5   1   0   2   0   1   1   0   0   1   0   0   0   0   0   0
!
!Ipr Ppl Ioc Mat Pcr Ls1 Ls2 Ls3 Syo Prf Ins Rpa Sym Hkl Fou Sho Ana
   0   0   1   0   1   0   0   0   1   1   0   1   0   1   2   0   0
!
! lambda1 Lambda2    Ratio   Bkpos    Wdt    Cthm     muR   AsyLim   Rpolarz
 1.540560 1.544390  0.5000 90.0000 15.0000  0.7995  0.0000   80.00    0.0000
!
!NCY Eps R_at R_an R_pr R_gl     Thmin       Step       Thmax    PSD    Sent0
 10 0.01 0.60 0.60 0.60 0.80     10.0000     0.0100   150.0000  0.000  0.000
!
! Excluded regions (LowT  HighT)
        1.00       10.00
      150.00      170.00
! 
!
      60    !Number of refined parameters
!
!  Zero    Code    Sycos    Code   Sysin    Code  Lambda     Code MORE
  0.0950  141.00  0.0000    0.00  0.0032  121.00 0.000000    0.00   0
!   Background coefficients/codes
  203.25     -142.55      404.23      601.18     -862.14     -1367.2    
      11.000      21.000      31.000      41.000      51.000      61.000
!-------------------------------------------------------------------------------
!  Data for PHASE number:   1  ==> Current R_Bragg:     3.24
!-------------------------------------------------------------------------------
   Na5Cr3F14 ??                                                       
!
!Nat Dis Mom Pr1 Pr2 Pr3 Jbt Irf Isy Str Furth     ATZ   Nvk Npr More
  13   0   0 1.0 0.0 0.0   0   0   0   0   0        0.00   0   5   0
!
P 21/N                   <--Space group symbol
!Atom Typ       X        Y        Z     Biso      Occ     In Fin N_t  /Codes
CR1  CR+3    0.00000  0.00000  0.00000  0.81624  0.50000   0   0   0
                0.00     0.00     0.00   421.00     0.00
CR2  CR+3    0.00000 -0.50000  0.00000  0.81624  0.50000   0   0   0
                0.00     0.00     0.00   511.00     0.00
CR3  CR+3    0.00000  0.00000  0.50000  0.81624  0.50000   0   0   0
                0.00     0.00     0.00   521.00     0.00
NA1  NA+1    0.24815 -0.29537  0.23214  2.32138  1.00000   0   0   0
              151.00   161.00   171.00   431.00     0.00
NA2  NA+1    0.24418 -0.23082  0.71992  2.32138  1.00000   0   0   0
              181.00   191.00   201.00   531.00     0.00
NA3  NA+1    0.00000 -0.50000  0.50000  0.82138  0.50000   0   0   0
                0.00     0.00     0.00   541.00     0.00
F1   F-1     0.11566 -0.48872 -0.19181  1.60745  1.00000   0   0   0
              211.00   221.00   231.00   441.00     0.00
F2   F-1     0.13429  0.16474  0.53039  1.60745  1.00000   0   0   0
              241.00   251.00   261.00   551.00     0.00
F3   F-1    -0.10967  0.20043  0.54343  1.60745  1.00000   0   0   0
              271.00   281.00   291.00   561.00     0.00
F4   F-1     0.03485 -0.24676  0.06737  1.60745  1.00000   0   0   0
              301.00   311.00   321.00   571.00     0.00
F5   F-1    -0.12601 -0.44067 -0.17694  1.60745  1.00000   0   0   0
              331.00   341.00   351.00   581.00     0.00
F6   F-1     0.17565  0.03977 -0.00912  1.60745  1.00000   0   0   0
              361.00   371.00   381.00   591.00     0.00
F7   F-1     0.00002  0.07200  0.24582  1.60745  1.00000   0   0   0
              391.00   401.00   411.00   601.00     0.00
!  Scale       Shape1      Bov     Str1     Str2     Str3    Strain-Model
 0.56663E-02   0.4239   0.0000   0.0000   0.0000   0.0000       0
   451.00000   461.00     0.00     0.00     0.00     0.00
!      U        V         W          X         Y       GauSiz   LorSiz Size-Model
   0.00255   0.00090   0.00205   0.00483   0.00000   0.00000   0.00000   0
    491.00    481.00    471.00    131.00      0.00      0.00      0.00
!     a          b         c        alpha      beta       gamma
  10.509578   7.225283   7.271332  90.000000  90.675354  90.000000
   81.00000   91.00000  101.00000    0.00000  111.00000    0.00000
!  Pref1  Pref2   Asy1    Asy2    Asy3     Asy4
 1.00000 0.00000 0.06045 0.00056 0.00000 0.00000
    0.00    0.00  501.00   71.00    0.00    0.00
The final result is shown in the following .sul FULLPROF file :
 
        ********************************************************
        ** PROGRAM FULLPROF.98 (Version 0.2  - Mar98-LLB JRC) **
        ********************************************************
           Rietveld, Profile Matching & Integrated Intensity
                Refinement of X-ray and/or Neutron Data


    Date: 09/03/2000  Time: 15:21:41.620                              

 => PCR file code: na5
 => DAT file code: na5
 => Title:   Na5Cr3F14  ??                                                      

 ==> CONDITIONS OF THIS RUN:

 => Global Refinement of X-ray powder diffraction data                          
    Bragg-Brentano or Debye-Scherrer geometry
 => The    5th default profile function was selected
 => Data supplied in free format 
 => Wavelengths:  1.54056 1.54439
 => Cos(Monochromator angle)=   0.7995
 => Absorption correction (muR-eff):   0.0000
 => Base of peaks: 2.0*HW*   15.00
 ==> Angular range, step and number of points:
     2Thmin:  10.0000  2Thmax: 150.0000  Step:   0.0100  No. of points:  14001
 => Crystal Structure Refinement for phase: 1
 => Scor: 1.4856

 ==> RESULTS OF REFINEMENT:


 => No. of fitted parameters:   60


------------------------------------------------------------------------------
 => Phase No.  1    Na5Cr3F14 ??                         P 21/N              
------------------------------------------------------------------------------

 =>  No. of reflections:   2264


 ==> ATOM PARAMETERS:

  Name    x     sx       y     sy       z      sz      B   sB  occ.  socc.

 CR1   0.00000(   0)  0.00000(   0)  0.00000(   0)  0.474(  6)  0.500(  0)
 CR2   0.00000(   0) -0.50000(   0)  0.00000(   0)  0.797(  8)  0.500(  0)
 CR3   0.00000(   0)  0.00000(   0)  0.50000(   0)  0.718(  7)  0.500(  0)
 NA1   0.24793(   6) -0.29532(   7)  0.23174(   8)  1.155( 12)  1.000(  0)
 NA2   0.24354(   6) -0.23092(   8)  0.71919(   9)  2.495( 16)  1.000(  0)
 NA3   0.00000(   0) -0.50000(   0)  0.50000(   0)  3.140( 21)  0.500(  0)
 F1    0.11488(   6) -0.48831(  10) -0.19280(   9)  1.798( 18)  1.000(  0)
 F2    0.13435(   7)  0.16452(  10)  0.52962(  10)  1.844( 21)  1.000(  0)
 F3   -0.10973(   6)  0.19977(  10)  0.54397(  10)  1.593( 19)  1.000(  0)
 F4    0.03450(   7) -0.24697(   9)  0.06798(  10)  1.588( 17)  1.000(  0)
 F5   -0.12715(   7) -0.44018(  10) -0.17783(   9)  1.552( 19)  1.000(  0)
 F6    0.17580(   6)  0.04025(  10) -0.00967(  10)  2.056( 19)  1.000(  0)
 F7   -0.00003(   8)  0.07193(   9)  0.24676(  11)  2.182( 18)  1.000(  0)

 ==> PROFILE PARAMETERS:

 => Cell parameters      :
                             10.50959   0.00001
                              7.22529   0.00001
                              7.27133   0.00001
                             90.00000   0.00000
                             90.67531   0.00006
                             90.00000   0.00000
 
 => overall scale factor :    0.005670784   0.000003652
 => Eta(p-v) or m(p-vii) :    0.42776   0.00217
 => Overall tem. factor  :    0.00000   0.00000
 => Halfwidth parameters :    0.00260   0.00004
                              0.00089   0.00003
                              0.00203   0.00001
 => Preferred orientation:    1.00000   0.00000
                              0.00000   0.00000
 => Asymmetry parameters :    0.05628   0.00114
                              0.00045   0.00017
                              0.00000   0.00000
                              0.00000   0.00000
 => X and y parameters   :    0.00466   0.00005
                              0.00000   0.00000
 => Strain parameters    :    0.00000   0.00000
                              0.00000   0.00000
                              0.00000   0.00000
 => Size   parameters    :    0.00000   0.00000
                              0.00000   0.00000

 ==> GLOBAL PARAMETERS:

 => Zero-point:   0.0945  0.0001
 => Background Polynomial Parameters ==>
                              189.152    0.480015    
                             -167.773     1.88409    
                              449.249     5.51788    
                              662.940     11.3522    
                             -935.337     13.4736    
                             -1447.58     19.3529    
 
 => Cos( theta)-shift parameter :   0.0000  0.0000
 => Sin(2theta)-shift parameter :   0.0036  0.0001

 ==> RELIABILITY FACTORS WITH ALL NON-EXCLUDED POINTS:

 => Cycle: 10 => MaxCycle: 10
 => N-P+C: 13940
 => Rp: 1.86     Rwp: 2.98     Rexp:    2.81 Chi2:  1.13      L.S. refinement
 => Conventional Rietveld R-factors ==>
 => Rp: 2.29     Rwp: 3.51     Rexp:    3.31 Chi2:  1.13    
 => Deviance: 0.158E+05     Dev*  :  1.133    
 => DW-Stat.:    1.7860     DW-exp:     1.9562
 => N-sigma of the GoF:   10.505

 ==> RELIABILITY FACTORS FOR POINTS WITH BRAGG CONTRIBUTIONS:

 => N-P+C: 13251
 => Rp: 1.82     Rwp: 2.92     Rexp:    2.76 Chi2:  1.12      L.S. refinement
 => Conventional Rietveld R-factors ==>
 => Rp: 2.21     Rwp: 3.41     Rexp:    3.23 Chi2:  1.12    
 => Deviance: 0.149E+05     Dev*  :  1.127    
 => DW-Stat.:    1.8890     DW-exp:     1.9553
 => N-sigma of the GoF:        9.755
 => Phase:  1
 => Bragg R-factor: 0.456       Vol:  552.109( 0.001)  Fract(%):    0.00( 0.00)
 => Rf-factor=0.509             ATZ:    0.000          Brindley:  1.0000
 

 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 

This is too good ! You will have some explanation Week-10 why this is too good. In standard cases, you may expect Rp in the range 7-12% for a quite good fit, and the Bragg R factor in the range 3-5%. Larger R values are of course possible but would be indicative of some difficulties. Smaller values are possible but quite rare.

No interest here in trying to refine anisotropic thermal parameters. We do not mean that this is always nonsense. From neutron data on PbSO4, this would probably feasible (see the RRRR - Rietveld Refinement Round Robin), or from X-ray data on the Pb atom only.


1- Pb2CrF7

We will do the job as if only Pb and Cr atoms had been located before Rietveld refinement.

At week-6 the coordinates proposed by the SHELXS-97 direct methods, and then refined by using SHELXL-97, were :
 

   "PbF2/CrF3/HFaq" ???  P21/c                                              

ATOM           x         y         z          sof         U      

Pb1         0.21861   0.18445   0.05435     1.00000     0.01683
  0.01290   0.00133   0.00076   0.00082     0.00000     0.00456

Pb2         0.24052   0.56295   0.13631     1.00000     0.01793
  0.01070   0.00125   0.00052   0.00063     0.00000     0.00468

Cr1         0.28704   0.87394   0.20097     1.00000     0.01141
  0.03835   0.00490   0.00204   0.00273     0.00000     0.01016


R1 =  0.2479 for    261 Fo > 4sig(Fo)  and  0.2505 for all    270 data
wR2 =  0.7832,  GooF = S =  11.707,  Restrained GooF =   11.707  for all data

We have to build the FULLPROF .pcr file, using the previous file built for structure factors extraction (week-5). Of course, we should use the pattern where the contribution of the CrF3 impurity is the smallest. This time again, we will only refine the scale factor of the main phase (pbcr.pcr) :
 
COMM   PbCr  ??                                                           
! Files => DAT-file: pbcr,  PCR-file: pbcr
!Job Npr Nph Nba Nex Nsc Nor Dum Iwg Ilo Ias Res Ste Nre Cry Uni Cor
   0   5   2  11   2   0   1   1   0   0   1   0   0   0   0   0   0
!
!Ipr Ppl Ioc Mat Pcr Ls1 Ls2 Ls3 Syo Prf Ins Rpa Sym Hkl Fou Sho Ana
   0   0   1   0   1   0   0   0   1   1   0   1   0   1   2   0   0
!
! lambda1 Lambda2    Ratio   Bkpos    Wdt    Cthm     muR   AsyLim   Rpolarz
 1.540560 1.544390  0.5000 90.0000 15.0000  0.7995  0.0000   80.00    0.0000
!
!NCY Eps R_at R_an R_pr R_gl     Thmin       Step       Thmax    PSD    Sent0
 10 0.01 0.60 0.60 0.60 0.80      5.0000     0.0100   150.0000  0.000  0.000
!
!  2Theta/TOF   Background
        5.000      530.760
        6.920      489.660
        9.080      446.920
       13.880      389.390
       16.760      358.160
       22.040      333.500
       27.570      312.130
       39.810      287.470
       84.940      256.240
      112.070      246.380
      150.000      267.750
! 
! Excluded regions (LowT  HighT)
        1.00       10.00
      150.00      170.00
! 
!
       1    !Number of refined parameters
!
!  Zero    Code    Sycos    Code   Sysin    Code  Lambda     Code MORE
  0.0337  121.00  0.0000    0.00  0.0000    0.00 0.000000    0.00   0
!-------------------------------------------------------------------------------
!  Data for PHASE number:   1  ==> Current R_Bragg:     1.82
!-------------------------------------------------------------------------------
   PbCr ??                                                            
!
!Nat Dis Mom Pr1 Pr2 Pr3 Jbt Irf Isy Str Furth     ATZ   Nvk Npr More
   3   0   0 1.0 0.0 0.0   0   0   0   0   0        0.00   0   5   0
!
P 21/C                   <--Space group symbol
PB1  PB+2    0.21861  0.18445  0.05435  1.00000  1.00000   0   0   0
                0.00     0.00     0.00     0.00     0.00
PB2  PB+2    0.24052  0.56295  0.13631  1.00000  1.00000   0   0   0
                0.00     0.00     0.00     0.00     0.00
CR   CR+3    0.28704  0.87394  0.20097  0.50000  1.00000   0   0   0
                0.00     0.00     0.00     0.00     0.00
!  Scale       Shape1      Bov     Str1     Str2     Str3    Strain-Model
 0.14573E-03   0.7855   0.0000   0.0000   0.0000   0.0000       0
    11.00000    21.00     0.00     0.00     0.00     0.00
!      U        V         W          X         Y       GauSiz   LorSiz Size-Model
   0.01160   0.00031   0.00182   0.00000   0.00000   0.00000   0.00000   0
     51.00     41.00     31.00      0.00      0.00      0.00      0.00
!     a          b         c        alpha      beta       gamma
   5.462546  11.208424   9.573616  90.000000  91.196121  90.000000
   81.00000   91.00000  101.00000    0.00000  111.00000    0.00000
!  Pref1  Pref2   Asy1    Asy2    Asy3     Asy4
 1.00000 0.00000 0.02525 0.00100 0.00000 0.00000
    0.00    0.00   61.00   71.00    0.00    0.00
!-------------------------------------------------------------------------------
!  Data for PHASE number:   2  ==> Current R_Bragg:     1.63
!-------------------------------------------------------------------------------
   CrF3                                                               
!
!Nat Dis Mom Pr1 Pr2 Pr3 Jbt Irf Isy Str Furth     ATZ   Nvk Npr More
   2   0   0 1.0 0.0 0.0   0   0   0   0   0        0.00   0   5   0
!
R -3 C                   <--Space group symbol
!Atom Typ       X        Y        Z     Biso      Occ     In Fin N_t  /Codes
CR   CR+3    0.00000  0.00000  0.00000  0.50000  0.06000   0   0   0
                0.00     0.00     0.00     0.00     0.00
F    F-1     0.60000  0.00000  0.25000  0.80000  0.18000   0   0   0
                0.00     0.00     0.00     0.00     0.00
!  Scale       Shape1      Bov     Str1     Str2     Str3    Strain-Model
 0.14573E-01   0.7855   0.0000   0.0000   0.0000   0.0000       0
   151.00000    21.00     0.00     0.00     0.00     0.00
!      U        V         W          X         Y       GauSiz   LorSiz Size-Model
   0.01160   0.00031   0.00182   0.00000   0.00000   0.00000   0.00000   0
     51.00     41.00     31.00      0.00      0.00      0.00      0.00
!     a          b         c        alpha      beta       gamma
   4.976699   4.976699  13.144844  90.000000  90.000000 120.000000
  131.00000  131.00000  141.00000    0.00000    0.00000  131.00000
!  Pref1  Pref2   Asy1    Asy2    Asy3     Asy4
 1.00000 0.00000 0.02525 0.00100 0.00000 0.00000
    0.00    0.00   61.00   71.00    0.00    0.00


The fit is already impressive :


 

And the reliability factors are much smaller than those produced by the SHELXL-97 refinement using the extracted structure factors. In principle R1 from SHELX can be compared to RF from the Rietveld method. We had R1 = 25 % and we have RF = 7.3 %, as seen in the FULLPROF .sum file, without refining nothing but the scale factor. This gives an idea of the weak contribution of the F atoms in that structure :
 

 

        ********************************************************
        ** PROGRAM FULLPROF.98 (Version 0.2  - Mar98-LLB JRC) **
        ********************************************************
           Rietveld, Profile Matching & Integrated Intensity
                Refinement of X-ray and/or Neutron Data


    Date: 10/03/2000  Time: 16:07:52.220                              

 => PCR file code: pbcr
 => DAT file code: pbcr
 => Title:   PbCr  ??                                                           

 ==> CONDITIONS OF THIS RUN:

 => Global Refinement of X-ray powder diffraction data                          
    Bragg-Brentano or Debye-Scherrer geometry
 => The    5th default profile function was selected
 => Data supplied in free format 
 => Wavelengths:  1.54056 1.54439
 => Cos(Monochromator angle)=   0.7995
 => Absorption correction (muR-eff):   0.0000
 => Base of peaks: 2.0*HW*   15.00
 ==> Angular range, step and number of points:
     2Thmin:   5.0000  2Thmax: 150.0000  Step:   0.0100  No. of points:  14501
 => Crystal Structure Refinement for phase: 1
 => Crystal Structure Refinement for phase: 2
 => Scor: 7.6344

 ==> RESULTS OF REFINEMENT:


 => No. of fitted parameters:    1


------------------------------------------------------------------------------
 => Phase No.  1    PbCr ??                              P 21/C              
------------------------------------------------------------------------------

 =>  No. of reflections:   2403


 ==> ATOM PARAMETERS:

  Name    x     sx       y     sy       z      sz      B   sB  occ.  socc.

 PB1   0.21861(   0)  0.18445(   0)  0.05435(   0)  1.000(  0)  1.000(  0)
 PB2   0.24052(   0)  0.56295(   0)  0.13631(   0)  1.000(  0)  1.000(  0)
 CR    0.28704(   0)  0.87394(   0)  0.20097(   0)  0.500(  0)  1.000(  0)

 ==> PROFILE PARAMETERS:

 => Cell parameters      :
                              5.46255   0.00000
                             11.20842   0.00000
                              9.57362   0.00000
                             90.00000   0.00000
                             91.19613   0.00000
                             90.00000   0.00000
 
 => overall scale factor :    0.000265872   0.000000575
 => Eta(p-v) or m(p-vii) :    0.78550   0.00000
 => Overall tem. factor  :    0.00000   0.00000
 => Halfwidth parameters :    0.01160   0.00000
                              0.00031   0.00000
                              0.00182   0.00000
 => Preferred orientation:    1.00000   0.00000
                              0.00000   0.00000
 => Asymmetry parameters :    0.02525   0.00000
                              0.00100   0.00000
                              0.00000   0.00000
                              0.00000   0.00000
 => X and y parameters   :    0.00000   0.00000
                              0.00000   0.00000
 => Strain parameters    :    0.00000   0.00000
                              0.00000   0.00000
                              0.00000   0.00000
 => Size   parameters    :    0.00000   0.00000
                              0.00000   0.00000

------------------------------------------------------------------------------
 => Phase No.  2    CrF3                                 R -3 C              
------------------------------------------------------------------------------

 =>  No. of reflections:    140


 ==> ATOM PARAMETERS:

  Name    x     sx       y     sy       z      sz      B   sB  occ.  socc.

 CR    0.00000(   0)  0.00000(   0)  0.00000(   0)  0.500(  0)  0.060(  0)
 F     0.60000(   0)  0.00000(   0)  0.25000(   0)  0.800(  0)  0.180(  0)

 ==> PROFILE PARAMETERS:

 => Cell parameters      :
                              4.97670   0.00000
                              4.97670   0.00000
                             13.14484   0.00000
                             90.00000   0.00000
                             90.00000   0.00000
                            120.00000   0.00000
 
 => overall scale factor :    0.014573000   0.000000000
 => Eta(p-v) or m(p-vii) :    0.78550   0.00000
 => Overall tem. factor  :    0.00000   0.00000
 => Halfwidth parameters :    0.01160   0.00000
                              0.00031   0.00000
                              0.00182   0.00000
 => Preferred orientation:    1.00000   0.00000
                              0.00000   0.00000
 => Asymmetry parameters :    0.02525   0.00000
                              0.00100   0.00000
                              0.00000   0.00000
                              0.00000   0.00000
 => X and y parameters   :    0.00000   0.00000
                              0.00000   0.00000
 => Strain parameters    :    0.00000   0.00000
                              0.00000   0.00000
                              0.00000   0.00000
 => Size   parameters    :    0.00000   0.00000
                              0.00000   0.00000

 ==> GLOBAL PARAMETERS:

 => Zero-point:   0.0337  0.0000
 => Cos( theta)-shift parameter :   0.0000  0.0000
 => Sin(2theta)-shift parameter :   0.0000  0.0000

 ==> RELIABILITY FACTORS WITH ALL NON-EXCLUDED POINTS:

 => Cycle:  2 => MaxCycle: 10
 => N-P+C: 13998
 => Rp: 11.6     Rwp: 16.5     Rexp:    3.05 Chi2:  29.4      L.S. refinement
 => Conventional Rietveld R-factors ==>
 => Rp: 15.6     Rwp: 21.1     Rexp:    3.88 Chi2:  29.4    
 => Deviance: 0.465E+06     Dev*  :  33.21    
 => DW-Stat.:    0.1032     DW-exp:     1.9478
 => N-sigma of the GoF: 2377.642

 ==> RELIABILITY FACTORS FOR POINTS WITH BRAGG CONTRIBUTIONS:

 => N-P+C: 13361
 => Rp: 11.7     Rwp: 16.7     Rexp:    3.00 Chi2:  30.8      L.S. refinement
 => Conventional Rietveld R-factors ==>
 => Rp: 15.5     Rwp: 21.0     Rexp:    3.79 Chi2:  30.8    
 => Deviance: 0.464E+06     Dev*  :  34.73    
 => DW-Stat.:    0.1034     DW-exp:     1.9465
 => N-sigma of the GoF:     2432.603
 => Phase:  1
 => Bragg R-factor:  14.5       Vol:  586.031( 0.000)  Fract(%):    0.00( 0.00)
 => Rf-factor= 7.27             ATZ:    0.000          Brindley:  1.0000
 => Phase:  2
 => Bragg R-factor:  5.79       Vol:  281.948( 0.000)  Fract(%):    0.00( 0.00)
 => Rf-factor= 4.40             ATZ:    0.000          Brindley:  1.0000

 => Run finished at:     Date: 10/03/2000  Time: 16:08:16.060
With such a good result, we can now refine all parameters, including two thermal parameters (one for the Cr atom and one for the two Pb atoms). That step is realized with the fp90.exe program, in order to obtain a correct .fou file (fp98 is a beta version with some bugs (? from our point of view, we don't know if this is not the author's desire ) at this step, sometimes). The .sum file is below, showing that a few % were gained :
 
 

        *******************************************************
        *** PROGRAM FULLPROF (Version 3.3  - Aug97-LLB JRC) ***
        *******************************************************
           Rietveld, Profile Matching & Integrated Intensity
                Refinement of X-ray and/or Neutron Data


    Date: 03/13/00  Time: 15:50:44.84   

 => PCR file code: pbcr
 => DAT file code: pbcr
 => Title:   PbCr  ??                                                           

 ==> CONDITIONS OF THIS RUN:

 => Global Refinement of X-ray powder diffraction data                          
    Bragg-Brentano or Debye-Scherrer geometry
 => The    5th default profile function was selected
 => Data supplied in free format 
 => Wavelengths:  1.54056 1.54439
 => Base of peaks: 2.0*HW*   15.00
 => Cos(Monochromator angle)=   0.7995
 => Absorption correction (muR-eff):   0.0000
 ==> Angular range, step and number of points:
     2Thmin:   5.0000  2Thmax: 150.0000  Step:   0.0100  No. of points:  14501
 => Crystal Structure Refinement for phase: 1
 => Crystal Structure Refinement for phase: 2
 => Scor: 7.0213

 ==> RESULTS OF REFINEMENT:


 => No. of fitted parameters:   27


------------------------------------------------------------------------------
 => Phase No.  1    PbCr ??                              P 21/C              
------------------------------------------------------------------------------

 =>  No. of reflections:   2403


 ==> ATOM PARAMETERS:

  Name    x     sx       y     sy       z      sz      B   sB  occ.  socc.

 PB1   0.21935(  28)  0.18913(  14)  0.05528(  16)  1.029( 29)  1.000(  0)
 PB2   0.23843(  29)  0.56035(  15)  0.13402(  15)  1.240( 32)  1.000(  0)
 CR    0.29400( 101)  0.86764(  51)  0.20427(  58)  0.316(120)  1.000(  0)

 ==> PROFILE PARAMETERS:

 => Cell parameters      :
                              5.46354   0.00005
                             11.21106   0.00011
                              9.57593   0.00010
                             90.00000   0.00000
                             91.19402   0.00069
                             90.00000   0.00000
 
 => Overall scale factor :    0.000271658   0.000001122
 => ETA(p-V) or M(P-VII) :    0.64675   0.00762
 => Overall Tem. factor  :    0.00000   0.00000
 => Halfwidth parameters :    0.02743   0.00087
                             -0.01386   0.00076
                              0.00608   0.00016
 => Preferred orientation:    1.00000   0.00000
                              0.00000   0.00000
 => Asymmetry parameters :    0.15855   0.00307
                             -0.01270   0.00107
                              0.00000   0.00000
                              0.00000   0.00000
 => X and Y parameters   :    0.00000   0.00000
                              0.00000   0.00000
 => Strain parameters    :    0.00000   0.00000
                              0.00000   0.00000
                              0.00000   0.00000
 => Size   parameters    :    0.00000   0.00000
                              0.00000   0.00000

------------------------------------------------------------------------------
 => Phase No.  2    CrF3                                 R -3 C              
------------------------------------------------------------------------------

 =>  No. of reflections:    140


 ==> ATOM PARAMETERS:

  Name    x     sx       y     sy       z      sz      B   sB  occ.  socc.

 CR    0.00000(   0)  0.00000(   0)  0.00000(   0)  0.500(  0)  0.060(  0)
 F     0.60000(   0)  0.00000(   0)  0.25000(   0)  0.800(  0)  0.180(  0)

 ==> PROFILE PARAMETERS:

 => Cell parameters      :
                              4.97771   0.00005
                              4.97771   0.00005
                             13.14706   0.00022
                             90.00000   0.00000
                             90.00000   0.00000
                            120.00000   0.00000
 
 => Overall scale factor :    0.015101586   0.000085291
 => ETA(p-V) or M(P-VII) :    0.64675   0.00762
 => Overall Tem. factor  :    0.00000   0.00000
 => Halfwidth parameters :    0.02743   0.00087
                             -0.01386   0.00076
                              0.00608   0.00016
 => Preferred orientation:    1.00000   0.00000
                              0.00000   0.00000
 => Asymmetry parameters :    0.15855   0.00307
                             -0.01270   0.00107
                              0.00000   0.00000
                              0.00000   0.00000
 => X and Y parameters   :    0.00000   0.00000

                              0.00000   0.00000
 => Strain parameters    :    0.00000   0.00000
                              0.00000   0.00000
                              0.00000   0.00000
 => Size   parameters    :    0.00000   0.00000
                              0.00000   0.00000

 ==> GLOBAL PARAMETERS:

 => Zero-point:   0.0531  0.0004
 => Cos( theta)-shift parameter :   0.0000  0.0000
 => Sin(2theta)-shift parameter :   0.0000  0.0000

 ==> RELIABILITY FACTORS WITH ALL NON-EXCLUDED POINTS:

 => Cycle: 10 => MaxCycle: 10
 => N-P+C: 13972
 => Rp: 11.0     Rwp: 15.6     Rexp:    3.05 Chi2:  26.4      L.S. refinement
 => Conventional Rietveld R-factors ==>
 => Rp: 14.9     Rwp: 19.9     Rexp:    3.88 Chi2:  26.4    
 => Deviance: 0.416E+06     Dev*  :  29.76    
 => DW-Stat.:    0.1389     DW-exp:     1.9515
 => N-sigma of the GoF: 2120.825

 ==> RELIABILITY FACTORS FOR POINTS WITH BRAGG CONTRIBUTIONS:

 => N-P+C: 13605
 => Rp: 11.1     Rwp: 15.7     Rexp:    3.02 Chi2:  27.1      L.S. refinement
 => Conventional Rietveld R-factors ==>
 => Rp: 14.8     Rwp: 19.9     Rexp:    3.83 Chi2:  27.1    
 => Deviance: 0.416E+06     Dev*  :  30.54    
 => DW-Stat.:    0.1390     DW-exp:     1.9509
 => N-sigma of the GoF:     2149.244
 => Phase:  1
 => Bragg R-factor:  12.9       Vol:     586.419   Fract(%):     0.00
 => Rf-factor= 6.18             ATZ:       0.000   Brindley:   1.0000
 => Phase:  2
 => Bragg R-factor:  4.52       Vol:     282.110   Fract(%):     0.00
 => Rf-factor= 3.59             ATZ:       0.000   Brindley:   1.0000
A Fourier synthesis will be calculated by the SHELXL-97 program, from the "|Fobs|" produced by the Rietveld decomposition formula (pbcr.fou). At the end of this document, another approach will be proposed, by using the GFOUR program. Remember that the "|Fobs|" depends on the |Fcalc| in that formula, so that a Fourier synthesis is less efficient than from single crystal data. Moreover, in that normal use of the Rietveld decomposition formula, only one iteration is performed, contrarily to what happens in the Le Bail method for "|Fobs|" extraction. In a first aproach, we will not use the OVERLAP program, and try the whole dataset. Below is the SHELXL .ins file :
 
TITL   "PbF2/CrF3/HFaq" ???  P21/c 
CELL 1.54056  5.46255 11.20846 9.57362 90.0 91.19608 90.0 
ZERR 2 0.001 0.001 0.001 0. 0.001 0.
LATT 1 
SYMM X,0.5-Y,0.5+Z 
SFAC PB CR F 
UNIT 8 4 28 
L.S. 4 
BOND 
ACTA
FMAP 2 
PLAN -10 
FVAR 1
PB1   1     0.21861    0.18445    0.05435    11.00000    0.01266
PB2   1     0.24052    0.56295    0.13631    11.00000    0.01266
CR    2     0.28704    0.87394    0.20097    11.00000    0.00633
HKLF 3                                                                          
END


We retrieve the R1 value equivalent to the Rietveld RB value after the SHELXL refinement :
 

   "PbF2/CrF3/HFaq" ???  P21/c                                              

ATOM           x         y         z          sof         U11       U22       U33       U23       U13       U12        Ueq

Pb1         0.21949   0.18912   0.05528     1.00000     0.01534
  0.00046   0.00005   0.00002   0.00003     0.00000     0.00040

Pb2         0.23830   0.56038   0.13397     1.00000     0.01790
  0.00054   0.00005   0.00002   0.00003     0.00000     0.00040

Cr          0.29464   0.86749   0.20458     1.00000     0.00546
  0.00194   0.00017   0.00008   0.00013     0.00000     0.00044



Final Structure Factor Calculation for    "PbF2/CrF3/HFaq" ???  P21/c                                              

Total number of l.s. parameters =    13     Maximum vector length =  511      Memory required =    420 /   21973

wR2 =  0.1822 before cycle   5 for   1206 data and     0 /    13 parameters

GooF = S =     0.242;     Restrained GooF =      0.242  for      0 restraints

Weight = 1 / [ sigma^2(Fo^2) + ( 0.1000 * P )^2 +   0.00 * P ]   where  P = ( Max ( Fo^2, 0 ) + 2 * Fc^2 ) / 3

R1 =  0.0737 for     82 Fo > 4sig(Fo)  and  0.0612 for all   1206 data
wR2 =  0.1822,  GooF = S =   0.242,  Restrained GooF =    0.242  for all data

An we look at the Fourier difference in the pbcr.lst file :
 
Atom       Peak    x       y       z     Sof  Height      Distances and Angles

PB1        2.12  0.2195  0.1891  0.0553 1.000  3.3   0 PB2       4.230
                                                     0 8         1.984  94.3
                                                     0 5         2.199  28.8  90.6
                                                     0 7         2.274  25.6  78.4  14.8
                                                   116 10        2.404  87.7  90.9 116.4 107.7
                                                     0 2         2.446  91.6  50.9  67.5  66.0 141.7
                                                    79 6         2.576  66.3  30.1  71.6  57.0  79.3  65.5
                                                     0 9         2.595 137.0  48.4 138.7 126.7  74.6  80.2  72.0
                                                     0 1         2.851  81.9 158.9  76.1  90.2 109.6 108.3 146.8 140.8
                                                    31 1         2.968  69.3  86.7  97.6  88.5  19.2 132.9  67.4  85.7 110.8
                                                    48 3         2.971 134.6 129.1 124.3 139.0 102.1 105.3 158.8  87.8  53.0 118.9
                                                    37 2         3.162  89.2 155.1 103.8 112.0  64.7 153.7 137.4 116.0  45.9  71.5
                                                     0 3         3.197 133.7  99.6 161.4 156.2  48.4 130.8 110.5  54.5  98.0  67.7
                                                     0 4         3.222  42.0 126.4  64.5  67.0  64.3 132.0  96.5 138.8  62.4  54.0
                                                     0 6         3.301  88.8  99.6  61.2  72.1 169.2  48.6 108.5 114.5  59.8 157.7
                                                   106 9         3.449 136.7  85.3 107.9 114.6 135.6  55.2 113.0  70.1  83.5 153.3
                                                     0 10        3.655  71.9 149.3  64.0  78.2 115.1 101.0 135.2 151.0  12.2 112.2
                                                    22 CR        3.730 105.7 159.5 104.8 118.6  94.3 122.6 169.8 114.2  28.8 104.3
                                                    23 CR        3.767 107.4  75.9  78.7  84.0 160.4  29.7  95.1  85.9  85.4 162.1
                                                    20 CR        3.897 147.4  73.8 164.2 150.2  62.9 102.8  93.2  26.1 119.5  79.7

PB2        1.79  0.2383  0.5604  0.1340 1.000  2.8   0 PB1       4.230
                                                   114 10        2.153 129.4
                                                   101 8         2.366 126.7  68.3
                                                    66 5         2.385 101.2 128.6  90.1
                                                     0 7         2.391  24.3 152.3 116.9  79.0
                                                    56 4         2.430  92.5  97.2 139.1  69.0  93.9
                                                    52 3         2.511  75.9  61.6  74.7 157.1  92.6 133.3
                                                    29 1         2.528 146.1  24.4  73.5 106.2 168.8  79.2  86.0
                                                     0 5         2.536  24.7 152.4 129.3  76.7  13.1  80.9  99.7 157.2
                                                   110 9         2.550  81.0 104.9  46.8  89.4  70.9 155.9  67.8 118.5  83.9
                                                    85 7         2.579  97.5 128.9 101.8  12.7  78.1  56.7 167.4 104.7  72.9 100.9
                                                    76 6         2.628 152.0  66.5  30.0  72.1 132.5 109.3  99.6  58.6 140.2  71.9
                                                     0 4         2.832  49.6  84.5 134.7 134.5  73.3  77.5  60.4  96.5  68.2 113.8
                                                    39 2         2.968 145.9  74.1  82.3  56.6 132.4  56.9 135.0  50.1 124.5 120.1
                                                    21 CR        3.520 176.3  47.0  54.6  82.1 159.4  87.1 101.7  30.3 158.2 100.8
                                                    25 CR        3.662  60.6  69.1 103.3 161.5  83.4 106.6  28.9  90.1  84.9  90.5
                                                    55 4         3.836  59.5 153.4  86.6  56.8  36.4 107.8 104.5 154.3  45.2  49.1
                                                    12 PB2       3.862  61.5 165.4 114.6  39.7  40.8  71.0 132.8 141.0  36.9  85.6
                                                    44 2         3.914 123.2  50.7  22.5 111.9 124.4 141.6  55.8  63.4 137.4  55.6
                                                    26 CR        3.966  61.2 127.2  69.7  81.1  47.3 135.6  77.7 142.4  60.1  24.0

CR         0.94  0.2946  0.8675  0.2046 1.000  2.5  20 6         1.839
                                                     7 1         1.847  86.4
                                                    12 3         1.902 174.0  87.8
                                                    16 4         1.936  92.5  96.4  89.5
                                                    29 9         1.937  95.7 166.4  89.6  96.9
                                                    10 2         2.040  79.7  74.6  97.4 168.4  92.5
                                                    32 10        2.588  71.3  19.8 103.3  84.3 167.1  85.0
                                                    28 8         2.887  19.9  72.8 156.6  80.0 112.4  90.1  55.1
                                                    25 7         2.930  52.7 122.0 132.4  54.1  68.8 124.3 102.2  55.3
                                                    19 5         3.483  53.5 119.9 131.4  51.2  71.3 126.8 100.1  54.7   3.2
                                                     4 PB2       3.520  46.8  43.6 127.3 111.1 132.0  57.4  37.5  41.9  96.6  96.4
                                                    11 2         3.523  49.6  76.8 130.1  46.8 114.7 122.6  57.4  33.6  45.9  43.4
                                                    33 10        3.525 145.6 123.7  40.2  69.9  59.2 121.1 132.4 146.6  94.1  93.9
                                                     6 PB2       3.662 142.3  94.3  39.7  49.9  92.2 136.7  98.3 127.0  97.3  95.3
                                                     2 PB1       3.730 122.3  48.1  52.2 121.4 121.1  57.9  68.0 116.7 170.1 167.5
                                                    27 8         3.806  86.5  90.6  92.2 172.8  76.2  17.1 102.0 100.8 120.6 123.6
                                                    26 8         3.848 104.0 165.9  81.5  92.6   9.1  97.6 174.2 119.6  72.0  74.2

                                                     1 PB1       3.897 130.1 136.7  54.6 103.1  36.1  88.5 156.0 148.2 100.5 102.3
                                                    17 5         3.972  44.5  75.2 132.2 135.9  97.0  35.3  73.8  56.0  93.4  95.1
                                                    13 3         3.987 130.9  96.1  48.5 135.4  72.4  54.4 115.6 144.5 141.1 143.7
1          1.36  0.4943  0.2593 -0.1809 1.000  2.0   0 PB1       2.851
                                                     0 PB2       4.754  61.7
                                                     0 10        1.056 133.2  78.2
                                                    22 CR        1.847 103.0 144.7 123.8
                                                    37 2         2.362  74.0  88.3 130.7  56.4
                                                    75 6         2.524 134.7 120.0  85.1  46.7  61.2
                                                    13 PB2       2.528 113.1  59.8  57.5 106.1  74.7  62.7
                                                    48 3         2.600  65.9 127.4 149.1  47.0  73.2  93.6 146.6
                                                    59 4         2.821 124.4 171.4  93.6  43.0  99.1  61.1 117.9  59.6
                                                   100 8         2.930 155.6 109.8  58.6  70.2  83.2  26.6  50.7 116.0  67.2
                                                     5 PB1       2.968 117.6 104.5  48.6 110.6 165.6 105.9 106.0 102.9  67.6  86.3
                                                     0 6         3.092  67.3  82.3  85.2 123.2 140.1 153.1 129.8  82.1  94.6 136.4
                                                     0 5         3.153  42.6  29.4  90.7 145.3 100.2 148.6  89.0 105.3 150.3 137.5
                                                     0 4         3.161  64.6  35.1  96.4 110.2  54.2  92.4  49.0 114.5 150.7  95.0
                                                    50 3         3.438 131.7  72.4  10.7 123.7 120.6  80.8  46.8 158.3  99.9  54.7
                                                    99 8         3.474  85.1  78.6  63.0 134.4 158.8 140.0 111.6 101.6  95.5 116.8
                                                    41 2         3.586 169.5 127.0  51.6  73.1 110.3  49.2  77.5 105.6  46.3  32.9
                                                     0 7         3.653  38.5  29.5  95.1 140.7  95.4 146.5  89.2 102.4 151.7 139.0
                                                    89 7         3.692  93.4 120.5  86.6  90.3 138.8 115.4 143.9  66.0  55.7 109.8
                                                   107 9         3.758  97.7 138.1 128.9   7.0  49.9  48.2 104.5  46.0  49.8  73.2

2          1.35 -0.2156  0.1972 -0.0096 1.000  4.0   0 PB1       2.446
                                                     0 PB2       4.946  58.7
                                                     0 8         1.950  52.2  74.4
                                                    23 CR        2.040 113.9 129.9 145.1
                                                    28 1         2.362 145.3 106.0 160.2  49.0
                                                     0 6         2.491  83.9  84.3 136.1  46.6  62.6
                                                     0 7         2.575  53.8   4.9  71.7 130.2 110.0  83.8
                                                     0 5         2.590  51.7  15.0  80.6 117.7 104.9  71.2  12.9
                                                    55 4         2.613 105.1  50.1  87.3 127.2  78.7 107.8  54.7  63.2
                                                    79 6         2.720  59.6  53.3  26.8 171.3 139.7 133.5  52.1  63.8  61.5
                                                   106 9         2.874  80.4 130.1 103.7  42.3  91.2  62.5 126.1 115.6 168.8 129.0
                                                    49 3         2.963 133.8 163.1 121.7  39.5  57.1  86.0 166.5 156.3 121.0 139.8
                                                    12 PB2       2.968  99.7  51.3 124.4  87.3  55.2  56.7  54.9  50.3  51.1  99.3
                                                   117 10        3.045 108.1  98.0  56.2 127.7 104.7 167.1  99.5 112.4  65.3  54.4
                                                   113 10        3.153 132.7  92.3 159.9  54.8  14.7  54.5  95.9  90.3  72.6 133.6
                                                     0 9         3.249  51.9 100.1  33.9 111.2 153.8 119.5  96.1  99.9 120.8  60.5
                                                    47 3         3.253 103.3 134.8  63.7  95.0 107.8 138.3 133.7 144.1 109.6  81.7
                                                    26 CR        3.523  86.8  52.6  55.0 157.5 108.9 133.5  54.8  67.5  32.7  31.0
                                                    99 8         3.539  90.0  75.3 140.3  54.7  55.3  15.4  76.0  64.4  92.6 128.1
                                                    33 1         3.586 103.1  82.7  54.7 139.7 105.5 158.9  84.5  97.4  51.3  44.6

3          1.30  0.5555 -0.0298  0.1542 1.000  3.2   0 PB1       3.197
                                                    20 CR        1.902  96.4
                                                   116 10        2.408  48.3 109.2
                                                    18 PB2       2.511 100.1 111.4  51.9
                                                    30 1         2.600 136.7  45.2 147.0 111.4
                                                    63 4         2.702 106.2  45.8  82.8  65.7  64.3
                                                     0 9         2.704  51.4  45.7  72.5 107.5  90.2  64.8
                                                   105 9         2.821 120.1 142.4  90.8  56.8 102.1 109.5 162.7
                                                    96 8         2.960  81.8 160.4  55.4  50.4 141.3 115.9 126.2  39.5
                                                    38 2         2.963  89.8  43.1 131.4 153.9  49.7  88.5  60.7 136.6 155.6
                                                     3 PB1       2.971 120.3  97.5 151.5 127.0  61.1 124.3 124.1  73.1 100.3  64.4
                                                    48 3         3.076  56.5 103.9  99.1 139.8 106.9 146.6  83.8 103.9  91.4  65.2
                                                    37 2         3.253  58.7 153.3  63.0  84.5 149.7 144.5 110.0  64.2  36.2 120.9
                                                    31 1         3.438  53.0 109.7   4.7  47.2 144.7  80.5  75.2  87.8  53.9 135.0
                                                    93 7         3.545 141.9  94.0  93.7  42.4  72.0  58.4 122.8  52.1  76.5 121.5
                                                   115 10        3.547 140.5  45.2 139.8 102.9   8.8  57.0  91.0  99.4 137.2  57.1
                                                    77 6         3.736  98.7   2.9 112.0 112.5  42.4  46.8  48.4 140.5 162.3  41.7
                                                    72 5         3.859 137.5  88.8  90.2  40.4  71.8  51.2 115.3  58.7  79.9 120.2
                                                   107 9         3.870  89.9 132.8 109.6 113.4 103.2 163.9 127.8  61.5  66.8  90.4
                                                    80 6         3.926  75.3 146.0  41.4  41.3 146.9 104.1 113.6  50.4  15.0 162.6

4          1.22  0.6248  0.3952  0.1002 1.000  2.2   0 PB1       3.222
                                                     0 PB2       2.832  88.4
                                                    25 CR        1.936  99.0  98.6
                                                    84 7         2.382 126.1 144.6  84.8
                                                    13 PB2       2.430 104.3 102.5 148.8  64.8
                                                    37 2         2.613  64.6 149.0 100.5  61.8  72.0
                                                    52 3         2.702  94.4  53.9  44.7 121.5 149.8 138.2
                                                    65 5         2.726 122.4 143.6  95.2  10.5  54.7  58.0 131.5
                                                    80 6         2.729  94.7 140.8  42.3  53.7 114.4  61.2  86.9  62.0
                                                    31 1         2.821  58.4  96.7  40.6 107.8 154.0  82.5  56.1 115.2  54.1
                                                   111 9         2.898 140.4  94.5  41.6  65.0 113.4 116.0  57.6  74.3  59.6  82.1
                                                     0 5         3.020  41.1  51.2 117.1 153.8  94.0  98.0  84.6 143.8 133.7  84.3
                                                   116 10        3.074  44.8 108.0  56.9 103.3 134.1  64.1  75.5 107.7  54.0  20.0
                                                     0 7         3.137  41.9  46.9 106.9 163.4 104.2 103.7  74.4 154.1 128.7  76.4
                                                     0 1         3.161  53.0 104.9 141.9  92.6  51.8  47.1 144.2  83.4 108.0 106.3
                                                    96 8         3.185  78.1 154.7  63.2  55.8 101.6  37.7 105.4  59.8  24.1  58.0
                                                    67 5         3.224 150.2  82.6 110.4  63.6  51.0 112.9 102.8  61.1 110.2 150.8
                                                    56 4         3.310  99.1  45.8 139.1 112.6  56.7 120.4  97.5 105.4 165.1 139.4
                                                   114 10        3.388 124.1  39.2  77.7 109.3 105.1 171.2  44.9 113.4 114.2 100.9
                                                     0 10        3.442  66.4  95.3 159.6  92.5  38.3  60.9 145.4  82.2 121.7 122.9

5          1.20  0.0933  0.3719  0.0113 1.000  3.1   0 PB1       2.199
                                                     0 PB2       2.536 126.4
                                                     0 7         0.581  90.0  69.1
                                                    12 PB2       2.385 129.7 103.3 103.1
                                                     0 2         2.590  60.8 149.6  82.1  73.1
                                                    55 4         2.726 108.8  93.5  48.6  56.3  58.8
                                                    79 6         2.809  60.5  95.8  31.1 113.1  60.4  59.1
                                                     0 6         2.957  78.1 150.3 133.6  57.8  52.9  93.0 112.3
                                                     0 8         2.976  41.8 121.1  56.5 109.0  40.3  67.8  26.1  88.1
                                                     0 4         3.020  74.4  60.5  96.2 148.3 135.1 143.8  96.4 122.2 102.6
                                                    85 7         3.040 175.7  54.2  94.1  50.6 121.2  75.1 123.8 100.1 142.3 103.7
                                                    66 5         3.054 173.0  49.4  83.1  53.9 119.3  67.5 113.0 107.8 133.1 104.8
                                                     0 1         3.153  61.3 112.9 146.6 108.4  96.4 152.7 121.4  60.7 101.7  61.5
                                                    56 4         3.224 131.9  48.1 116.5  84.9 154.3 118.9 143.6 104.1 165.2  63.9
                                                     0 10        3.338  79.7 104.0 160.7  96.1 106.4 150.5 139.8  60.4 119.5  65.3
                                                    99 8         3.361  99.2 127.6 142.8  44.7  71.6  94.6 131.9  22.9 109.8 121.0
                                                   110 9         3.399 108.1  48.2  22.0  99.5 101.8  55.2  52.6 148.1  78.4  89.1
                                                   108 9         3.473 124.7  94.6 143.3  47.2 103.3 102.9 159.6  55.8 142.9 103.9
                                                    26 CR        3.483  91.8  80.8  16.2  89.6  69.1  33.6  31.8 118.4  52.4 112.2
                                                    28 1         3.928  92.6 137.2  97.4  38.2  35.5  53.1  88.6  40.0  74.5 161.1

6          1.11 -0.0615  0.2447 -0.2463 1.000  3.0   0 PB1       3.301
                                                    99 8         1.315 132.5
                                                    23 CR        1.839  89.6 131.8
                                                    89 7         2.331 115.7  91.2  88.4
                                                     0 2         2.491  47.5 134.5  53.7 132.5
                                                    28 1         2.524 103.1  94.2  46.9 120.3  56.2
                                                     5 PB1       2.576 115.2  49.2 141.5  54.9 161.8 139.0
                                                    12 PB2       2.628  88.1  63.9 102.6 154.1  70.8  58.7 107.0
                                                   113 10        2.652 118.9  70.9  67.6 119.2  75.6  23.4 117.1  48.1
                                                    43 2         2.720 170.1  41.9  99.4  60.7 142.2  86.2  54.9  94.1  69.0
                                                    60 4         2.729 129.6  97.8  45.1  55.5  98.4  64.8  98.4 117.8  69.7  57.3
                                                   106 9         2.801  68.3 156.6  43.5  67.2  65.5  89.6 117.0 135.6 111.1 115.7
                                                    71 5         2.809 119.5  84.1  94.8   7.4 139.9 122.9  48.0 147.6 118.3  55.8
                                                     0 5         2.957  40.7  96.1 109.6 147.1  56.0  91.2 108.2  50.1  93.5 137.3

                                                   108 9         3.040 105.7  26.8 149.3 107.6 119.5 102.9  54.3  52.9  81.7  68.4
                                                     0 1         3.092  52.8  95.5 132.4  84.6 100.1 153.1  62.4 103.9 151.9 117.3
                                                     0 10        3.182  68.6  76.2 151.5  85.1 113.9 153.4  47.9  95.1 138.7 101.5
                                                     0 7         3.384  39.8 100.1 102.7 151.6  49.2  85.1 115.3  48.8  89.3 140.1
                                                    49 3         3.736  89.8 130.2   3.0  91.0  52.3  44.0 143.5  99.6  64.9  99.3
                                                    51 3         3.926 127.0  35.8 104.0 115.7 101.9  59.8  84.8  39.1  36.9  55.1

7          1.09  0.0539  0.3749  0.0671 1.000  3.3   0 PB1       2.274
                                                     0 PB2       2.391 130.1
                                                     0 5         0.581  75.2  97.8
                                                    79 6         2.331  68.0 114.5 141.4

                                                    55 4         2.382 119.2 107.0 120.8  70.7
                                                     0 2         2.575  60.2 169.7  85.0  67.1  63.5
                                                    12 PB2       2.579 117.4 101.9  64.3 124.1  58.5  70.3
                                                     0 8         2.699  46.0 141.3 113.1  29.1  77.4  43.3 112.0
                                                   110 9         2.868 125.8  57.1 153.6  64.2  66.2 118.3 109.8  93.1
                                                    26 CR        2.930 106.0  95.8 160.6  38.9  41.1  79.3  99.4  61.6  39.0
                                                    66 5         3.040 161.1  50.4  85.9 130.7  71.8 120.3  52.9 149.0  71.9  92.2
                                                    85 7         3.135 150.5  53.6  75.3 141.0  78.0 118.3  48.3 154.7  82.3 102.2
                                                     0 4         3.137  71.1  59.8  73.2 104.4 163.4 130.3 130.8 106.4  97.3 125.9
                                                     0 6         3.384  68.1 133.0  39.2 112.5  89.6  47.0  50.1  84.6 155.6 122.5
                                                    56 4         3.522 116.4  43.5  55.0 156.2 119.5 136.4  76.2 162.3  98.8 134.3
                                                    52 3         3.545  94.6  45.0 118.7  76.4 116.7 141.2 146.1  97.9  50.9  80.6
                                                     0 1         3.653  51.3 101.7  28.3 119.1 141.6  85.4  91.2  95.8 152.1 157.2
                                                    31 1         3.692  53.5  85.1 109.1  56.5 125.5 103.4 170.8  63.6  79.0  85.7
                                                    99 8         3.840  85.3 114.7  31.9 130.5  89.3  63.4  37.1 103.7 146.7 128.8
                                                   108 9         3.954 105.4  85.6  31.6 158.7  97.3  91.8  39.3 132.7 128.2 137.0

8          1.03 -0.0694  0.1605  0.1729 1.000  4.2   0 PB1       1.984
                                                     0 PB2       4.804  61.4
                                                    79 6         1.315 100.8  44.3
                                                     0 2         1.950  76.9  82.6 111.4
                                                     0 9         1.959  82.3 137.0 135.6 112.4
                                                    16 PB2       2.366 148.0 130.2  86.1 129.9  71.5
                                                   117 10        2.544 159.9 110.0  79.9  84.2 111.4  51.8
                                                     0 7         2.699  55.6  18.1  59.7  64.9 137.8 145.1 110.1
                                                    26 CR        2.887 116.8  55.6  28.4  91.4 153.0  83.5  56.5  63.2
                                                    33 1         2.930 152.4  92.3  59.2  92.4 125.2  55.8  20.7  96.8  37.0
                                                    47 3         2.960 129.8 155.5 129.2  80.1  66.4  54.9  51.2 142.8 107.7  71.4
                                                     0 5         2.976  47.6  26.9  69.9  59.1 129.8 155.4 116.1  10.3  72.9 105.0
                                                   116 10        3.140  50.0  70.5  79.8 126.7  68.5 101.9 147.7  80.3 108.0 132.4
                                                    55 4         3.185  99.3  52.8  58.1  55.0 165.9 110.5  63.8  46.9  36.8  54.8
                                                    70 5         3.361 111.5  95.1  61.0 169.0  76.5  45.2  86.5 113.2  78.5  76.9
                                                    31 1         3.474  58.5  58.8  62.4 130.5  83.6  99.5 135.0  72.2  90.6 116.8
                                                    40 2         3.539 127.7  74.4  30.2 125.4 118.2  56.2  59.8  89.0  35.2  41.5
                                                    23 CR        3.806  73.7  96.3 129.1  17.9  94.6 125.4  90.2  78.2 108.6 103.2
                                                    91 7         3.840 116.7  96.8  60.2 164.3  78.7  41.1  81.3 114.9  75.6  71.9
                                                    20 CR        3.848  76.5 128.4 129.3 116.9   9.0  75.1 118.8 131.1 151.4 130.4

9          1.03  0.0674 -0.0010  0.1816 1.000  4.3   0 PB1       2.595
                                                    20 CR        1.937 117.9
                                                     0 8         1.959  49.3 162.0
                                                    16 PB2       2.550 108.8 123.6  61.7
                                                     0 3         2.704  74.2  44.7 118.8 139.5
                                                    77 6         2.801 155.3  40.8 154.7  95.7  85.4
                                                    47 3         2.821 112.2 123.7  74.1  55.5 162.7  83.8
                                                    95 7         2.868 150.6  72.2 112.9  52.0 105.6  48.5  77.1
                                                    38 2         2.874 105.3  45.2 142.6 143.1  64.1  52.0  98.6 100.5
                                                    63 4         2.898 118.6  41.5 128.1  89.3  57.5  57.2 125.4  48.8  86.5
                                                   116 10        3.032  49.9  87.5  74.5 100.5  49.2 123.9 147.2 107.0 112.2  69.6
                                                    79 6         3.040  53.7 147.6  17.6  55.2 111.6 150.2  84.0 102.1 157.3 110.5
                                                     0 2         3.249  47.9 151.7  33.7  84.0 119.1 141.6  64.4 133.5 109.7 160.5
                                                    74 5         3.399 147.0  76.1 108.6  47.9 107.9  52.8  76.0   4.4 104.8  50.5
                                                     1 PB1       3.449 109.9  83.7 111.7 109.0 107.4  62.7  55.5  98.3  44.4 118.5
                                                    70 5         3.473  94.3 101.5  70.2  43.4  96.7 101.9  98.8  56.3 146.4  60.0
                                                   106 9         3.539  66.4 103.6  83.2 123.6  95.2 102.7  74.0 141.3  59.8 144.7
                                                   117 10        3.735  87.7 153.9  39.4  33.9 156.2 115.4  40.1  82.7 137.4 123.0
                                                    30 1         3.758 114.9   6.6 162.6 129.5  43.8  42.2 122.8  77.6  38.9  48.1
                                                    97 8         3.836  87.9  74.5 113.6 138.8  80.6  75.0  83.4 121.4  29.6 116.0

10         0.89  0.4903  0.3356 -0.2457 1.000  1.7   0 PB1       3.655
                                                     0 PB2       4.654  59.8
                                                     0 1         1.056  34.7  89.0
                                                    13 PB2       2.153  97.9  62.0  98.1
                                                     5 PB1       2.404 108.7 119.6 112.2 149.6
                                                    50 3         2.408 141.8  82.5 164.6  66.5  83.2
                                                   100 8         2.544 130.5 121.8 100.7  59.8 109.2  73.4
                                                    22 CR        2.588  71.0 119.9  36.4  95.5 106.8 141.7  68.5
                                                    75 6         2.652 102.6 119.9  71.5  65.4 120.4 101.7  29.2  41.1
                                                   108 9         3.032  97.9  67.2 129.5 107.2  55.6  58.3 129.8 156.1 159.0
                                                    41 2         3.045 146.0 152.0 112.6  96.2  69.8  72.2  39.6  77.0  56.5 107.2
                                                    59 4         3.074  96.0 155.2  66.3 121.7  70.9 122.1  68.3  38.8  56.3 126.4
                                                    99 8         3.140  78.1  83.3  99.5 140.6  39.2  92.3 147.7 119.1 154.0  37.0
                                                    37 2         3.153  54.7  82.0  34.6  64.9 143.8 130.7  76.0  40.1  49.9 147.1
                                                     0 6         3.182  57.2  83.1  75.5 144.8  52.7 115.9 155.0  98.4 138.7  58.5
                                                     0 5         3.338  36.3  31.9  70.8  91.1 101.5 106.7 148.9 107.2 131.5  65.9
                                                    56 4         3.388  89.7  30.3 118.8  56.3 108.2  52.3 107.2 144.0 121.5  53.3
                                                     0 4         3.442  53.9  37.3  65.9  44.5 154.2 100.2  96.2  86.4  84.2 104.4
                                                    24 CR        3.525 113.8  60.0 147.8  76.1  79.7  30.6 103.2 170.6 129.8  33.3
                                                    48 3         3.547  48.7 107.9  22.1 116.9  92.2 169.5  99.5  31.4  72.5 126.2


Examination of the connectivity list suggest that peaks Q1, Q2, Q3, Q4, Q6, Q9 form a reasonable CrF6 octahedron with the Cr atom. Peak number 10 is too close to peak 1, and should be eliminated. The same for peak 8, too close to peak 6. Peaks 5 and 7 are 0.5 angstrom apart, but one of them would make a good 7th fluorine atom, connected only to Pb atoms.

Possibly, a more clean Fourier difference synthesis would be obtained from a dataset reduced by using the overlap program.

We may have a look at the structure model by using the STRUPLO program, reading the .res file generated by SHELXL-97, and reorganized :
 

TITL   "PbF2/CrF3/HFaq" ???  P21/c
CELL 1.54056  5.46255 11.20846 9.57362 90.0 91.19608 90.0
ZERR 2 0.001 0.001 0.001 0. 0.001 0.
LATT 1
SYMM X,0.5-Y,0.5+Z
SFAC PB CR F
UNIT 8 4 28
L.S. 4
ACTA
BOND
FMAP 2
PLAN -10
WGHT    0.100000
FVAR       0.49932
PB1     1   0.21949   0.18912   0.05528    11.00000     0.01534
PB2     1   0.23830   0.56038   0.13397    11.00000     0.01790
CR      2   0.29464   0.86749   0.20458    11.00000     0.00546
Q1    1   0.4943  0.2593 -0.1809  11.00000  0.05    1.36
Q2    1  -0.2156  0.1972 -0.0096  11.00000  0.05    1.35
Q3    1   0.5555 -0.0298  0.1542  11.00000  0.05    1.30
Q4    1   0.6248  0.3952  0.1002  11.00000  0.05    1.22
Q5    1   0.0933  0.3719  0.0113  11.00000  0.05    1.20
Q6    1  -0.0615  0.2447 -0.2463  11.00000  0.05    1.11
Q9    1   0.0674 -0.0010  0.1816  11.00000  0.05    1.03
HKLF 3
END
The Struplo output is very conclusive, since the CrF6 octahedra appear with the default option :

You may modify the Struplo file, once saved, for making the Pb and "isolated" fluorine atoms to appear.

You will probably encounter cases where it will be better to enter only one supplementary atom in the Rietveld refinement, and to perform a new Fourier difference synthesis, etc. Here we will add all these suggested fluorine atoms in one run, and see what happens :

The new .pcr file becomes :
 

COMM   PbCr  ??                                                           
! Files => DAT-file: pbcr,  PCR-file: pbcr
!Job Npr Nph Nba Nex Nsc Nor Dum Iwg Ilo Ias Res Ste Nre Cry Uni Cor
   0   5   2  11   2   0   1   1   0   0   1   0   0   0   0   0   0
!
!Ipr Ppl Ioc Mat Pcr Ls1 Ls2 Ls3 Syo Prf Ins Rpa Sym Hkl Fou Sho Ana
   0   0   1   0   1   0   0   0   1   1   0   1   0   1   2   0   0
!
! lambda1 Lambda2    Ratio   Bkpos    Wdt    Cthm     muR   AsyLim   Rpolarz
 1.540560 1.544390  0.5000 90.0000 15.0000  0.7995  0.0000   80.00    0.0000
!
!NCY Eps R_at R_an R_pr R_gl     Thmin       Step       Thmax    PSD    Sent0
 10 0.01 0.40 0.40 0.40 0.80      5.0000     0.0100   150.0000   0.000   0.000
!
! 2Theta/TOF    Background
    5.00       530.76
    6.92       489.66
    9.08       446.92
   13.88       389.39
   16.76       358.16
   22.04       333.50
   27.57       312.13
   39.81       287.47
   84.94       256.24
  112.07       246.38
  150.00       267.75
! 
! Excluded regions (LowT  HighT)
        1.00       10.00
      150.00      170.00
! 
!
      49    !Number of refined parameters
!
!  Zero    Code    Sycos    Code   Sysin    Code  Lambda     Code MORE
  0.0531  121.00  0.0000    0.00  0.0000    0.00 0.000000    0.00   0
!
!  Data for PHASE number:   1  ==> Current R_Bragg:    12.93
   PbCr ??                                                            
!
!Nat Dis Mom Pr1 Pr2 Pr3 Jbt Irf Isy Str Furth     ATZ   Nvk Npr More
  10   0   0 1.0 0.0 0.0   0   0   0   0   0        0.00   0   5   0
!
P 21/C                   <--Space group symbol
!Atom Typ       X        Y        Z     Biso      Occ     In Fin N_t  /Codes
PB1  PB+2    0.21935  0.18913  0.05528  1.02945  1.00000   0   0   0
              161.00   171.00   181.00   191.00     0.00
PB2  PB+2    0.23843  0.56035  0.13402  1.23951  1.00000   0   0   0
              201.00   211.00   221.00   231.00     0.00
CR   CR+3    0.29400  0.86764  0.20427  0.31564  1.00000   0   0   0
              241.00   251.00   261.00   271.00     0.00
Q1   F-1     0.4943   0.2593  -0.1809   1.20000  1.00000   0   0   0
              281.00   291.00   301.00   491.00     0.00
Q2   F-1    -0.2156   0.1972  -0.0096   1.20000  1.00000   0   0   0
              311.00   321.00   331.00   491.00     0.00
Q3   F-1     0.5555  -0.0298   0.1542   1.20000  1.00000   0   0   0
              341.00   351.00   361.00   491.00     0.00
Q4   F-1     0.6248   0.3952   0.1002   1.20000  1.00000   0   0   0
              371.00   381.00   391.00   491.00     0.00
Q5   F-1     0.0933   0.3719   0.0113   1.20000  1.00000   0   0   0
              401.00   411.00   421.00   491.00     0.00
Q6   F-1    -0.0615   0.2447  -0.2463   1.20000  1.00000   0   0   0
              431.00   441.00   451.00   491.00     0.00
Q9   F-1     0.0674  -0.0010   0.1816   1.20000  1.00000   0   0   0
              461.00   471.00   481.00   491.00     0.00
!  Scale       Shape1      Bov     Str1     Str2     Str3    Strain-Model
 0.27166E-03   0.6467   0.0000   0.0000   0.0000   0.0000       0
    11.00000    21.00     0.00     0.00     0.00     0.00
!      U        V         W          X         Y       GauSiz   LorSiz Size-Model
   0.02743  -0.01386   0.00608   0.00000   0.00000   0.00000   0.00000   0
     51.00     41.00     31.00      0.00      0.00      0.00      0.00
!     a          b         c        alpha      beta       gamma
   5.463544  11.211061   9.575928  90.000000  91.194016  90.000000
   81.00000   91.00000  101.00000    0.00000  111.00000    0.00000
!  Pref1  Pref2   Asy1    Asy2    Asy3     Asy4
 1.00000 0.00000 0.15855-0.01270 0.00000 0.00000
    0.00    0.00   61.00   71.00    0.00    0.00
!
!  Data for PHASE number:   2  ==> Current R_Bragg:     4.52
   CrF3                                                               
!
!Nat Dis Mom Pr1 Pr2 Pr3 Jbt Irf Isy Str Furth     ATZ   Nvk Npr More
   2   0   0 1.0 0.0 0.0   0   0   0   0   0        0.00   0   5   0
!
R -3 C                   <--Space group symbol
!Atom Typ       X        Y        Z     Biso      Occ     In Fin N_t  /Codes
CR   CR+3    0.00000  0.00000  0.00000  0.50000  0.06000   0   0   0
                0.00     0.00     0.00     0.00     0.00
F    F-1     0.60000  0.00000  0.25000  0.80000  0.18000   0   0   0
                0.00     0.00     0.00     0.00     0.00
!  Scale       Shape1      Bov     Str1     Str2     Str3    Strain-Model
 0.15102E-01   0.6467   0.0000   0.0000   0.0000   0.0000       0
   151.00000    21.00     0.00     0.00     0.00     0.00
!      U        V         W          X         Y       GauSiz   LorSiz Size-Model
   0.02743  -0.01386   0.00608   0.00000   0.00000   0.00000   0.00000   0
     51.00     41.00     31.00      0.00      0.00      0.00      0.00
!     a          b         c        alpha      beta       gamma
   4.977706   4.977706  13.147063  90.000000  90.000000 120.000000
  131.00000  131.00000  141.00000    0.00000    0.00000  131.00000
!  Pref1  Pref2   Asy1    Asy2    Asy3     Asy4
 1.00000 0.00000 0.15855-0.01270 0.00000 0.00000
    0.00    0.00   61.00   71.00    0.00    0.00
The refinement starts with quite better R values :


 

And quickly, the reliabilities decrease :
 

 

        *******************************************************
        *** PROGRAM FULLPROF (Version 3.3  - Aug97-LLB JRC) ***
        *******************************************************
           Rietveld, Profile Matching & Integrated Intensity
                Refinement of X-ray and/or Neutron Data


    Date: 03/13/00  Time: 16:52:16.61   

 => PCR file code: pbcr
 => DAT file code: pbcr
 => Title:   PbCr  ??                                                           

 ==> CONDITIONS OF THIS RUN:

 => Global Refinement of X-ray powder diffraction data                          
    Bragg-Brentano or Debye-Scherrer geometry
 => The    5th default profile function was selected
 => Data supplied in free format 
 => Wavelengths:  1.54056 1.54439
 => Base of peaks: 2.0*HW*   15.00
 => Cos(Monochromator angle)=   0.7995
 => Absorption correction (muR-eff):   0.0000
 ==> Angular range, step and number of points:
     2Thmin:   5.0000  2Thmax: 150.0000  Step:   0.0100  No. of points:  14501
 => Crystal Structure Refinement for phase: 1
 => Crystal Structure Refinement for phase: 2
 => Scor: 3.5580

 ==> RESULTS OF REFINEMENT:


 => No. of fitted parameters:   49


------------------------------------------------------------------------------
 => Phase No.  1    PbCr ??                              P 21/C              
------------------------------------------------------------------------------

 =>  No. of reflections:   2405


 ==> ATOM PARAMETERS:

  Name    x     sx       y     sy       z      sz      B   sB  occ.  socc.

 PB1   0.21898(  11)  0.18752(   6)  0.05506(   6)  1.390( 12)  1.000(  0)
 PB2   0.23967(  11)  0.56103(   6)  0.13503(   6)  1.469( 12)  1.000(  0)
 CR    0.29952(  41)  0.86850(  24)  0.20624(  26)  0.790( 50)  1.000(  0)
 Q1    0.46696( 118)  0.25832(  60) -0.21118(  72)  1.364( 62)  1.000(  0)
 Q2   -0.21072( 110)  0.17989(  59) -0.02003(  63)  1.364( 62)  1.000(  0)
 Q3    0.55251( 114) -0.03279(  67)  0.14646(  62)  1.364( 62)  1.000(  0)
 Q4    0.60571( 111)  0.40343(  59)  0.10639(  64)  1.364( 62)  1.000(  0)
 Q5    0.12437( 111)  0.38388(  61)  0.00251(  70)  1.364( 62)  1.000(  0)
 Q6   -0.04613( 121)  0.24238(  62) -0.25853(  69)  1.364( 62)  1.000(  0)
 Q9    0.07832( 122) -0.00044(  59)  0.20126(  69)  1.364( 62)  1.000(  0)

 ==> PROFILE PARAMETERS:

 => Cell parameters      :
                              5.46269   0.00002
                             11.20868   0.00004
                              9.57393   0.00004
                             90.00000   0.00000
                             91.19644   0.00024
                             90.00000   0.00000
 
 => Overall scale factor :    0.000309702   0.000000421
 => ETA(p-V) or M(P-VII) :    0.77432   0.00305
 => Overall Tem. factor  :    0.00000   0.00000
 => Halfwidth parameters :    0.01869   0.00030
                             -0.00475   0.00024
                              0.00274   0.00005
 => Preferred orientation:    1.00000   0.00000
                              0.00000   0.00000
 => Asymmetry parameters :    0.05474   0.00260
                              0.00007   0.00039
                              0.00000   0.00000
                              0.00000   0.00000
 => X and Y parameters   :    0.00000   0.00000
                              0.00000   0.00000
 => Strain parameters    :    0.00000   0.00000
                              0.00000   0.00000
                              0.00000   0.00000
 => Size   parameters    :    0.00000   0.00000
                              0.00000   0.00000

------------------------------------------------------------------------------
 => Phase No.  2    CrF3                                 R -3 C              
------------------------------------------------------------------------------

 =>  No. of reflections:    140


 ==> ATOM PARAMETERS:

  Name    x     sx       y     sy       z      sz      B   sB  occ.  socc.

 CR    0.00000(   0)  0.00000(   0)  0.00000(   0)  0.500(  0)  0.060(  0)
 F     0.60000(   0)  0.00000(   0)  0.25000(   0)  0.800(  0)  0.180(  0)

 ==> PROFILE PARAMETERS:

 => Cell parameters      :
                              4.97683   0.00002
                              4.97683   0.00002
                             13.14515   0.00009
                             90.00000   0.00000
                             90.00000   0.00000
                            120.00000   0.00000
 
 => Overall scale factor :    0.014576116   0.000034674
 => ETA(p-V) or M(P-VII) :    0.77432   0.00305
 => Overall Tem. factor  :    0.00000   0.00000
 => Halfwidth parameters :    0.01869   0.00030
                             -0.00475   0.00024
                              0.00274   0.00005
 => Preferred orientation:    1.00000   0.00000
                              0.00000   0.00000
 => Asymmetry parameters :    0.05474   0.00260
                              0.00007   0.00039
                              0.00000   0.00000
                              0.00000   0.00000
 => X and Y parameters   :    0.00000   0.00000
                              0.00000   0.00000
 => Strain parameters    :    0.00000   0.00000
                              0.00000   0.00000
                              0.00000   0.00000
 => Size   parameters    :    0.00000   0.00000
                              0.00000   0.00000

 ==> GLOBAL PARAMETERS:

 => Zero-point:   0.0364  0.0003
 => Cos( theta)-shift parameter :   0.0000  0.0000
 => Sin(2theta)-shift parameter :   0.0000  0.0000

 ==> RELIABILITY FACTORS WITH ALL NON-EXCLUDED POINTS:

 => Cycle: 10 => MaxCycle: 10
 => N-P+C: 13950
 => Rp: 4.66     Rwp: 6.32     Rexp:    3.04 Chi2:  4.31      L.S. refinement
 => Conventional Rietveld R-factors ==>
 => Rp: 6.27     Rwp: 8.05     Rexp:    3.88 Chi2:  4.31    
 => Deviance: 0.592E+05     Dev*  :  4.241    
 => DW-Stat.:    0.6093     DW-exp:     1.9546
 => N-sigma of the GoF:  276.467

 ==> RELIABILITY FACTORS FOR POINTS WITH BRAGG CONTRIBUTIONS:

 => N-P+C: 13375
 => Rp: 4.66     Rwp: 6.33     Rexp:    3.00 Chi2:  4.44      L.S. refinement
 => Conventional Rietveld R-factors ==>
 => Rp: 6.19     Rwp: 8.00     Rexp:    3.79 Chi2:  4.44    
 => Deviance: 0.585E+05     Dev*  :  4.369    
 => DW-Stat.:    0.6164     DW-exp:     1.9538
 => N-sigma of the GoF:      281.582
 => Phase:  1
 => Bragg R-factor:  3.08       Vol:     586.080   Fract(%):     0.00
 => Rf-factor= 2.97             ATZ:       0.000   Brindley:   1.0000
 => Phase:  2
 => Bragg R-factor:  2.55       Vol:     281.969   Fract(%):     0.00
 => Rf-factor= 2.27             ATZ:       0.000   Brindley:   1.0000
We may try now to improve the fit by using the parametrized polynomial representation of the background, like in the previous Na5Al3F14 case. Of course, performing a final Fourier difference synthesis is necessary, but you will not find any new meaningful peak.

After several runs, adding more and more parameters, including separated U, V, W values for the 2 phases, here is the final .sum FULLPROF file :
 

 

        ********************************************************
        ** PROGRAM FULLPROF.98 (Version 0.2  - Mar98-LLB JRC) **
        ********************************************************
           Rietveld, Profile Matching & Integrated Intensity
                Refinement of X-ray and/or Neutron Data


    Date: 14/03/2000  Time: 08:51:07.770                              

 => PCR file code: pbcr
 => DAT file code: pbcr
 => Title:   PbCr  ??                                                           

 ==> CONDITIONS OF THIS RUN:

 => Global Refinement of X-ray powder diffraction data                          
    Bragg-Brentano or Debye-Scherrer geometry
 => The    5th default profile function was selected
 => Data supplied in free format 
 => Wavelengths:  1.54056 1.54439
 => Cos(Monochromator angle)=   0.7995
 => Absorption correction (muR-eff):   0.0000
 => Base of peaks: 2.0*HW*   15.00
 ==> Angular range, step and number of points:
     2Thmin:   5.0000  2Thmax: 150.0000  Step:   0.0100  No. of points:  14501
 => Crystal Structure Refinement for phase: 1
 => Crystal Structure Refinement for phase: 2
 => Scor: 1.5596

 ==> RESULTS OF REFINEMENT:


 => No. of fitted parameters:   65


------------------------------------------------------------------------------
 => Phase No.  1    PbCr ??                              P 21/C              
------------------------------------------------------------------------------

 =>  No. of reflections:   2403


 ==> ATOM PARAMETERS:

  Name    x     sx       y     sy       z      sz      B   sB  occ.  socc.

 PB1   0.21910(   6)  0.18751(   3)  0.05496(   3)  0.881(  7)  1.000(  0)
 PB2   0.23967(   6)  0.56094(   3)  0.13525(   3)  0.846(  8)  1.000(  0)
 CR    0.30080(  22)  0.86734(  12)  0.20739(  14)  0.430( 26)  1.000(  0)
 Q1    0.46853(  65)  0.26204(  34) -0.21435(  40)  1.198( 34)  1.000(  0)
 Q2   -0.21051(  61)  0.17795(  33) -0.02293(  35)  1.198( 34)  1.000(  0)
 Q3    0.55267(  63) -0.03313(  37)  0.14533(  34)  1.198( 34)  1.000(  0)
 Q4    0.60397(  61)  0.40591(  33)  0.10458(  35)  1.198( 34)  1.000(  0)
 Q5    0.12525(  62)  0.38461(  33)  0.00372(  39)  1.198( 34)  1.000(  0)
 Q6   -0.04344(  67)  0.24117(  34) -0.26094(  38)  1.198( 34)  1.000(  0)
 Q9    0.08395(  68) -0.00202(  33)  0.19897(  38)  1.198( 34)  1.000(  0)

 ==> PROFILE PARAMETERS:

 => Cell parameters      :
                              5.46257   0.00001
                             11.20845   0.00002
                              9.57377   0.00002
                             90.00000   0.00000
                             91.19705   0.00013
                             90.00000   0.00000
 
 => overall scale factor :    0.000296038   0.000000263
 => Eta(p-v) or m(p-vii) :    0.35651   0.00310
 => Overall tem. factor  :    0.00000   0.00000
 => Halfwidth parameters :    0.00375   0.00007
                              0.00121   0.00008
                              0.00247   0.00002
 => Preferred orientation:    1.00000   0.00000
                              0.00000   0.00000
 => Asymmetry parameters :    0.04592   0.00151
                              0.00260   0.00025
                              0.00000   0.00000
                              0.00000   0.00000
 => X and y parameters   :    0.01247   0.00006
                              0.00000   0.00000
 => Strain parameters    :    0.00000   0.00000
                              0.00000   0.00000
                              0.00000   0.00000
 => Size   parameters    :    0.00000   0.00000

                              0.00000   0.00000

------------------------------------------------------------------------------
 => Phase No.  2    CrF3                                 R -3 C              
------------------------------------------------------------------------------

 =>  No. of reflections:    140


 ==> ATOM PARAMETERS:

  Name    x     sx       y     sy       z      sz      B   sB  occ.  socc.

 CR    0.00000(   0)  0.00000(   0)  0.00000(   0)  0.519( 10)  0.060(  0)
 F     0.59541(  14)  0.00000(   0)  0.25000(   0)  0.922( 18)  0.180(  0)

 ==> PROFILE PARAMETERS:

 => Cell parameters      :
                              4.97679   0.00001
                              4.97679   0.00001
                             13.14501   0.00004
                             90.00000   0.00000
                             90.00000   0.00000
                            120.00000   0.00000
 
 => overall scale factor :    0.014619797   0.000029180
 => Eta(p-v) or m(p-vii) :    0.88953   0.00446
 => Overall tem. factor  :    0.00000   0.00000
 => Halfwidth parameters :    0.01229   0.00025
                             -0.00377   0.00022
                              0.00225   0.00004
 => Preferred orientation:    1.00000   0.00000
                              0.00000   0.00000
 => Asymmetry parameters :    0.03297   0.00220
                              0.00042   0.00050
                              0.00000   0.00000
                              0.00000   0.00000
 => X and y parameters   :    0.00000   0.00000
                              0.00000   0.00000
 => Strain parameters    :    0.00000   0.00000
                              0.00000   0.00000
                              0.00000   0.00000
 => Size   parameters    :    0.00000   0.00000
                              0.00000   0.00000

 ==> GLOBAL PARAMETERS:

 => Zero-point:   0.0352  0.0001
 => Background Polynomial Parameters ==>
                              182.741    0.736442    
                             -168.356     2.24982    
                              469.410     6.25947    
                              659.487     13.2592    
                             -977.614     14.8567    
                             -1453.49     21.8424    
 
 => Cos( theta)-shift parameter :   0.0000  0.0000
 => Sin(2theta)-shift parameter :   0.0000  0.0000

 ==> RELIABILITY FACTORS WITH ALL NON-EXCLUDED POINTS:

 => Cycle: 10 => MaxCycle: 10
 => N-P+C: 13934
 => Rp: 2.44     Rwp: 3.46     Rexp:    3.04 Chi2:  1.29      L.S. refinement
 => Conventional Rietveld R-factors ==>
 => Rp: 3.12     Rwp: 4.24     Rexp:    3.73 Chi2:  1.29    
 => Deviance: 0.181E+05     Dev*  :  1.298    
 => DW-Stat.:    1.6189     DW-exp:     1.9570
 => N-sigma of the GoF:   24.341

 ==> RELIABILITY FACTORS FOR POINTS WITH BRAGG CONTRIBUTIONS:

 => N-P+C: 13402
 => Rp: 2.42     Rwp: 3.42     Rexp:    3.00 Chi2:  1.30      L.S. refinement
 => Conventional Rietveld R-factors ==>
 => Rp: 3.05     Rwp: 4.17     Rexp:    3.66 Chi2:  1.30    
 => Deviance: 0.175E+05     Dev*  :  1.305    
 => DW-Stat.:    1.6732     DW-exp:     1.9563
 => N-sigma of the GoF:       24.505
 => Phase:  1
 => Bragg R-factor: 0.570       Vol:  586.045( 0.002)  Fract(%):    0.00( 0.00)
 => Rf-factor=0.416             ATZ:    0.000          Brindley:  1.0000
 => Phase:  2
 => Bragg R-factor: 0.510       Vol:  281.962( 0.001)  Fract(%):    0.00( 0.00)
 => Rf-factor=0.389             ATZ:    0.000          Brindley:  1.0000

 => Run finished at:     Date: 14/03/2000  Time: 09:10:28.340


Again, this is too much good !-).


 



Pb2CrF7, using GFOUR for Fourier synthesis :

GFOUR needs a .inp and a .fou files which are generated by FULLPROF (FP98) by selecting the option FOU=4 at line 3 in the .pcr file. We start at the step where Pb and Cr atoms aare already located and their coordinates refined :
 

COMM   PbCr  ??                                                           
! Files => DAT-file: pbcr,  PCR-file: pbcrg
!Job Npr Nph Nba Nex Nsc Nor Dum Iwg Ilo Ias Res Ste Nre Cry Uni Cor
   0   5   2  11   2   0   1   1   0   0   1   0   0   0   0   0   0
!
!Ipr Ppl Ioc Mat Pcr Ls1 Ls2 Ls3 Syo Prf Ins Rpa Sym Hkl Fou Sho Ana
   0   0   1   0   1   0   0   0   1   1   0   1   0   1   4   0   0
!
! lambda1 Lambda2    Ratio   Bkpos    Wdt    Cthm     muR   AsyLim   Rpolarz
 1.540560 1.544390  0.5000 90.0000 15.0000  0.7995  0.0000   80.00    0.0000
!
!NCY Eps R_at R_an R_pr R_gl     Thmin       Step       Thmax    PSD    Sent0
 10 0.01 0.60 0.60 0.60 0.80      5.0000     0.0100   150.0000  0.000  0.000
!
!  2Theta/TOF   Background
        5.000      530.760
        6.920      489.660
        9.080      446.920
       13.880      389.390
       16.760      358.160
       22.040      333.500
       27.570      312.130
       39.810      287.470
       84.940      256.240
      112.070      246.380
      150.000      267.750
! 
! Excluded regions (LowT  HighT)
        1.00       10.00
      150.00      170.00
! 
!
      27    !Number of refined parameters
!
!  Zero    Code    Sycos    Code   Sysin    Code  Lambda     Code MORE
  0.0531  121.00  0.0000    0.00  0.0000    0.00 0.000000    0.00   0
!-------------------------------------------------------------------------------
!  Data for PHASE number:   1  ==> Current R_Bragg:    12.93
!-------------------------------------------------------------------------------
   PbCr ??                                                            
!
!Nat Dis Mom Pr1 Pr2 Pr3 Jbt Irf Isy Str Furth     ATZ   Nvk Npr More
   3   0   0 1.0 0.0 0.0   0   0   0   0   0        0.00   0   5   0
!
P 21/C                   <--Space group symbol
!Atom Typ       X        Y        Z     Biso      Occ     In Fin N_t  /Codes
PB1  PB+2    0.21935  0.18913  0.05528  1.02946  1.00000   0   0   0
              161.00   171.00   181.00   191.00     0.00
PB2  PB+2    0.23843  0.56035  0.13402  1.23951  1.00000   0   0   0
              201.00   211.00   221.00   231.00     0.00
CR   CR+3    0.29400  0.86764  0.20427  0.31564  1.00000   0   0   0
              241.00   251.00   261.00   271.00     0.00
!  Scale       Shape1      Bov     Str1     Str2     Str3    Strain-Model
 0.27166E-03   0.6467   0.0000   0.0000   0.0000   0.0000       0
    11.00000    21.00     0.00     0.00     0.00     0.00
!      U        V         W          X         Y       GauSiz   LorSiz Size-Model
   0.02743  -0.01386   0.00608   0.00000   0.00000   0.00000   0.00000   0
     51.00     41.00     31.00      0.00      0.00      0.00      0.00
!     a          b         c        alpha      beta       gamma
   5.463544  11.211061   9.575928  90.000000  91.194016  90.000000
   81.00000   91.00000  101.00000    0.00000  111.00000    0.00000
!  Pref1  Pref2   Asy1    Asy2    Asy3     Asy4
 1.00000 0.00000 0.15855-0.01270 0.00000 0.00000
    0.00    0.00   61.00   71.00    0.00    0.00
!-------------------------------------------------------------------------------
!  Data for PHASE number:   2  ==> Current R_Bragg:     4.52
!-------------------------------------------------------------------------------
   CrF3                                                               
!
!Nat Dis Mom Pr1 Pr2 Pr3 Jbt Irf Isy Str Furth     ATZ   Nvk Npr More
   2   0   0 1.0 0.0 0.0   0   0   0   0   0        0.00   0   5   0
!
R -3 C                   <--Space group symbol
!Atom Typ       X        Y        Z     Biso      Occ     In Fin N_t  /Codes
CR   CR+3    0.00000  0.00000  0.00000  0.50000  0.06000   0   0   0
                0.00     0.00     0.00     0.00     0.00
F    F-1     0.60000  0.00000  0.25000  0.80000  0.18000   0   0   0
                0.00     0.00     0.00     0.00     0.00
!  Scale       Shape1      Bov     Str1     Str2     Str3    Strain-Model
 0.15102E-01   0.6467   0.0000   0.0000   0.0000   0.0000       0
   151.00000    21.00     0.00     0.00     0.00     0.00
!      U        V         W          X         Y       GauSiz   LorSiz Size-Model
   0.02743  -0.01386   0.00608   0.00000   0.00000   0.00000   0.00000   0
     51.00     41.00     31.00      0.00      0.00      0.00      0.00
!     a          b         c        alpha      beta       gamma
   4.977706   4.977706  13.147063  90.000000  90.000000 120.000000
  131.00000  131.00000  141.00000    0.00000    0.00000  131.00000
!  Pref1  Pref2   Asy1    Asy2    Asy3     Asy4
 1.00000 0.00000 0.15855-0.01270 0.00000 0.00000
    0.00    0.00   61.00   71.00    0.00    0.00


The pbcr.inp file which is now built as a default file (in which you will have to change some options) is the following :
 

  ! Template file to be used with the program FOURIER
  ! Title of the job
Titl     PbCr  ??                                                         

  ! Cell parameters
Cell      5.4635   11.2111    9.5759   90.0000   91.1940   90.0000

  ! Atoms in the asymmetric unit 
Atom  PB1      0.21935   0.18913   0.05528
Atom  PB2      0.23843   0.56035   0.13402
Atom  CR       0.29400   0.86764   0.20427

  ! Space group symbol
Spgr P 21/C              

  ! Type of Fourier synthesis 
Fourier Fobs           ->  Change Fobs by DIFF for a Fourier difference synthesis

  ! Name of the Fourier-reflection file
File  fou pbcrg.fou

  ! Format of the Fourier-reflection file
Form    h k l fo fc phase

  ! Standard output binary file
File   bin

  ! Peak search 
Scan  15

  ! End of file
End
And the .fou file contains the observed and calculated structure factors, as well as the phases :
 
 Phase no.:   1    PbCr ??                    
   0   1   1   63.1651   62.9904  180.0000
   0   2   0    9.8212   10.4816  180.0000
   1   0   0   50.9617   51.6332    0.0000
   1   1   0   70.4325   70.6533  180.0000
   0   2   1  106.0051  106.1186  180.0000
   0   0   2   90.0828   89.8764    0.0000
   1   1  -1   93.4067   93.9811  180.0000
   0   1   2   25.4863   25.6405  180.0000
   1   1   1   89.3754   89.5878    0.0000
   1   2   0   33.4734   34.5056  180.0000
   1   2  -1  197.7849  197.5818  180.0000
   0   2   2  154.7034  154.5342  180.0000
   1   0  -2  536.0651  535.5217    0.0000
etc
 

 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 

We may now start GFOUR, click on "File) and open the pbcrg.inp file :


 
 

Then, clicking on "Calculations", enad "Fourier", and a section of the Fourier map appears, with a lot of possibilities for visiting it in full details :


 
 

The summary of the calculation is in the pbcrg.out file, where we will find our 15 peaks asked to be found by automatic search :
 
 

 !***************************************************************************!
 !****  FOURIER  MAPS  CALCULATION  PROGRAM  (Version: Windows 9X / NT)  ****!
 !****  Copyright(c) 1999.                               Release: 01.06  ****!
 !****  Javier Gonzalez-Platas         &        Juan Rodriguez-Carvajal  ****!
 !****  E:\sdpd-co      Date: 14/03/2000                 Time: 09:47:14  ****!
 !***************************************************************************!
 
 !---------------------------------------------------------------------------!
 !----  FOURIER  MAPS  CALCULATION  PROGRAM  (Version: Windows 9X / NT)  ----!
 !----  Copyright(c) 1999.                               Release: 01.06  ----!
 !----                                                                   ----!
 !----  Files Information                                                ----!
 !---------------------------------------------------------------------------!
 
         Input Data:  E:\sdpd-course-solutions\week-9\data\pbcrg.inp                                                                          
        Output Data:  E:\sdpd-course-solutions\week-9\data\pbcrg.out                                                                          
        HKL- F Data:  pbcrg.fou                                                                                                               
        Binary Data:  E:\sdpd-course-solutions\week-9\data\pbcrg.bin                                                                          
         Peaks Data:  E:\sdpd-course-solutions\week-9\data\pbcrg.pks                                                                          
 
 
 !---------------------------------------------------------------------------!
 !----  FOURIER  MAPS  CALCULATION  PROGRAM  (Version: Windows 9X / NT)  ----!
 !----  Copyright(c) 1999.                               Release: 01.06  ----!
 !----                                                                   ----!
 !----  Cell Parameters Information                                      ----!
 !---------------------------------------------------------------------------!
 
 => Direct cell parameters:

         a =       5.4635      b =      11.2111      c =       9.5759
     alpha =       90.000   beta =       91.194  gamma =       90.000
                        Direct Cell Volume =     586.4142

 => Reciprocal cell parameters:

         a*=     0.183073      b*=     0.089197      c*=     0.104451
     alpha*=       90.000   beta*=       88.806  gamma*=       90.000
                    Reciprocal Cell Volume =   0.00170528

 => Direct and Reciprocal Metric Tensors:

                   GD                                       GR
     29.8498      0.0000     -1.0902          0.033516    0.000000    0.000398
      0.0000    125.6888      0.0000          0.000000    0.007956    0.000000
     -1.0902      0.0000     91.6979          0.000398    0.000000    0.010910

 =>  Crystal_to_Orthonormal_Matrix              Orthonormal_to_Crystal Matrix

              Cr_Orth_cel                               Orth_Cr_cel  
      5.4623      0.0000      0.0000          0.183073    0.000000    0.000000
      0.0000     11.2111      0.0000          0.000000    0.089197    0.000000
     -0.1138      0.0000      9.5759          0.002177    0.000000    0.104429
 
 
 !---------------------------------------------------------------------------!
 !----  FOURIER  MAPS  CALCULATION  PROGRAM  (Version: Windows 9X / NT)  ----!
 !----  Copyright(c) 1999.                               Release: 01.06  ----!
 !----                                                                   ----!
 !----  Space Group Information                                          ----!
 !---------------------------------------------------------------------------!
 
 =>          Space group: P 21/C              
 =>       N. Space group:  14
 =>       Crystal System: Monoclinic  
 =>           Laue Class: 2/m  
 =>          Point Group: 2/m  
 =>       Centrosymmetry: Centric 
 =>      Bravais Lattice:   P: { 000 }                                       
 =>       Lattice Symbol:  mP
 =>      Asymmetric unit:  0.000 <= x <=  1.000
                           0.000 <= y <=  0.250
                           0.000 <= z <=  1.000
 =>       Number of S.O.:   2
 => General multiplicity:   4
 => List of S.O. without inversion and lattice centring translations
 => SYMM( 1): x,y,z                 => SYMM( 2): -x,y+1/2,-z+1/2      
                                                                      
 
 !---------------------------------------------------------------------------!
 !----  FOURIER  MAPS  CALCULATION  PROGRAM  (Version: Windows 9X / NT)  ----!
 !----  Copyright(c) 1999.                               Release: 01.06  ----!
 !----                                                                   ----!
 !----  Fast Fourier Transform Information                               ----!
 !---------------------------------------------------------------------------!
 
       Type: Differ. (Fo-Fc)
 
       Grid Dimensions:    Nx =   22   Dx =  0.045
                           Ny =   46   Dy =  0.022
                           Nz =   38   Dz =  0.026
 
       Reflections used:     1269
 
                           H max =    6     H min =    0
                           K max =   14     K min =    0
                           L max =   16     L min =  -11
 
       F000 =      0.000             Scale =      1.000
 
       Density Max:        2.402     Density Min:       -1.943
 
 
 !---------------------------------------------------------------------------!
 !----  FOURIER  MAPS  CALCULATION  PROGRAM  (Version: Windows 9X / NT)  ----!
 !----  Copyright(c) 1999.                               Release: 01.06  ----!
 !----                                                                   ----!
 !----  Scan Peaks Information                                           ----!
 !---------------------------------------------------------------------------!
 
       Number of Peaks =    15
 
       Peak    x/a       y/b       z/c      Occ      Density
 
        1    0.7764    0.1856    0.9667    1.0000    1.5709
        2    0.4427    0.0316    0.8370    1.0000    1.6596
        3    0.0877    0.0045    0.2073    1.0000    1.5802
        4    0.6061    0.1012    0.6071    1.0000    1.5259
        5    0.2309    0.1736    0.0937    1.0000    1.4568
        6    0.7223    0.0691    0.3242    1.0000    1.3538
        7    0.4581    0.2493    0.2926    1.0000    1.3787
        8    0.2839    0.1734    0.0340    1.0000    1.2607
        9    0.8174    0.1586    0.3924    1.0000   -1.4434
       10    0.9348    0.2405    0.7604    1.0000    1.2146
       11    0.7436    0.0188    0.4811    1.0000   -1.0543
       12    0.2861    0.2462    0.4682    1.0000   -1.1870
       13    0.1125    0.1226    0.5078    1.0000    1.2901
       14    0.1478    0.0839    0.0706    1.0000   -1.0437
       15    0.2733    0.1270    0.9614    1.0000   -0.9006
 
 
 !---------------------------------------------------------------------------!
 !----  FOURIER  MAPS  CALCULATION  PROGRAM  (Version: Windows 9X / NT)  ----!
 !----  Copyright(c) 1999.                               Release: 01.06  ----!
 !----                                                                   ----!
 !----  List Control of Atom / Peaks                                     ----!
 !---------------------------------------------------------------------------!
 
    Atom     x/a       y/b      z/c   Peak    x/a      y/b      z/c     Dist
 
     PB1    0.2194   0.1891   0.0553   5    0.2309   0.1736   0.0937   0.411
     PB2    0.2384   0.5604   0.1340   6    0.7223   0.0691   0.3242   0.461
 
 
       Cpu Time:     1.12 secs
 
       Fourier Program finished OK
 
 !***************************************************************************!
 !****  E:\sdpd-co      Date: 14/03/2000                 Time: 09:47:15  ****!
 !****                                                                   ****!
 !****  Programme d'Actions Integrees Franco-Espagnol << PICASSO 1999 >> ****!
 !****                     (Dossier Num. 98186)                          ****!
 !****                                                                   ****!
 !***************************************************************************!
 

 
 
 
 
 
 
 
 
 
 
 
 
 
 
 

GFOUR is already saying that peaks 5 and 6 are too close from the Pb atoms.

Let us see if the positive peaks are really corresponding to F atoms by using STRUVIR/STRUPLO :
 

TITL  "PbF2/CrF3/HFaq" ???  P21/c
CELL     5.463  11.208   9.574  90.00  91.20  90.00
PARA   1.00  1  1  1  1  1  1  3.20  0.00  0.01
SYMM   +X,1/2-Y,1/2+Z
VIEW     0   0   1   0   0   0
XYZR   -0.50  1.50 -0.50  1.50 -0.50  1.50
TETR   109.0  20.0   1.62   0.20
OCTA    90.0  20.0   1.97   0.40
PERS       70.00
COLO  PB 2 CR 3 F 4 Q 5
CIRC 0.5 PB
END
PB   1     0.2195    0.1891    0.0553
PB   2     0.2383    0.5604    0.1340
CR   1     0.2946    0.8675    0.2046
Q    1    0.7764    0.1856    0.9667    1.0000    1.5709
Q    2    0.4427    0.0316    0.8370    1.0000    1.6596
Q    3    0.0877    0.0045    0.2073    1.0000    1.5802
Q    4    0.6061    0.1012    0.6071    1.0000    1.5259
Q    5    0.2309    0.1736    0.0937    1.0000    1.4568
Q    6    0.7223    0.0691    0.3242    1.0000    1.3538
Q    7    0.4581    0.2493    0.2926    1.0000    1.3787
Q    8    0.2839    0.1734    0.0340    1.0000    1.2607
Q   10    0.9348    0.2405    0.7604    1.0000    1.2146
Q   13    0.1125    0.1226    0.5078    1.0000    1.2901


The distance calculation (in STRUVIR but not in STRUPLO) shows that peaks 5 and 8 are not the only peaks too close to the Pb atoms. Peak 6 should also be eliminated. Then it is clear that peaks 1, 2, 3, 4, 7 and 10 will form a CrF6 octahedra. And peak 13 is a good candidate for being an isolated F atom, connected only to the Pb atoms.
 



K2TiF6

Just an example in order to show that you will not always obtain so easily very small reliability factors...

The first thing to do with that pattern, which you would not have any problem to identify by using the JCPDS-ICDD database, is to use the ICSD data for building a .pcr file for structure factor extraction purpose. But in fact, we just want to see how small can be the Rp and Rwp reliability factors when there is no structure constraint, but only cell constraint. This is always a good thing to do, in any case : verifying the cell, the space group, and having an idea of the limit of refinability of the pattern.

The ICSD file is below and seems complete :
 

 COL  ICSD Collection Code 24659
 DATE Recorded Oct 3, 1986; updated Oct 3, 1986
 NAME Potassium hexafluorotitanate
 FORM K2 Ti F6
      = F6 K2 Ti
 TITL The Crystal Structure of K2 Ti F6
 REF  Acta Crystallographica (1,1948-23,1967)
      ACCRA 5 (1952) 683-684
 AUT  Siegel S
 CELL a=5.715(2) b=5.715(2) c=4.656(1) alpha=90.0 beta=90.0 gamma=120.0
      V=131.7 D=3.07 Z=1
 SGR  P -3 m 1      (164) - trigonal
 CLAS -3m   (Hermann-Mauguin) - D3d (Schoenflies)
 PRS  hP9
 ANX  AB2X6
 PARM Atom__No OxStat  Wyck -----X----- -----Y----- -----Z-----  -SOF-
      K      1  1.000    2d  1/3         2/3         0.700(4)
      Ti     1  4.000    1a  0.          0.          0.
      F      1 -1.000    6i  0.156(3)    0.844(3)    0.244(4)
 WYCK i d a
 TEST Calculated density unusual but tolerable. (Code 23)
 TEST No R value given in the paper. (Code 51)
 TEST At least one temperature factor missing in the paper. (Code 53)
After evaluating manually the background (with DMPLOT), the .pcr for Le Bail fit is built. We use here the zeropoint and cell parameters refined by ERACEL, from peak positions estimated by PowderX and compared to the expected positions generated by HKLGEN :
 
COMM   K2TiF6 P-3m1                                                       
! Files => DAT-file: k2tif60,  PCR-file: k2tif60
!Job Npr Nph Nba Nex Nsc Nor Dum Iwg Ilo Ias Res Ste Nre Cry Uni Cor
   0   5   1  20   2   0   1   1   0   0   1   0   0   0   0   0   0
!
!Ipr Ppl Ioc Mat Pcr Ls1 Ls2 Ls3 Syo Prf Ins Rpa Sym Hkl Fou Sho Ana
   0   0   1   0   1   0   0   0   1   1   0   1   0   0   2   0   0
!
! lambda1 Lambda2    Ratio   Bkpos    Wdt    Cthm     muR   AsyLim   Rpolarz
 1.540560 1.544390  0.5000 90.0000 20.0000  0.7995  0.0000   90.00    0.0000
!
!NCY Eps R_at R_an R_pr R_gl     Thmin       Step       Thmax    PSD    Sent0
 20 0.01 0.40 0.40 0.40 0.80      5.0000     0.0200   130.0000  0.000  0.000
!
!  2Theta/TOF   Background
        5.000     4104.130
        6.050     3431.700
        8.110     2481.030
       10.590     1889.760
       12.870     1356.450
       14.730     1059.970
       16.190      864.180
       19.910      614.380
       23.230      523.230
       29.010      421.960
       33.770      391.580
       47.430      364.580
       60.690      334.190
       74.970      303.810
       95.450      256.550
      100.010      256.550
      104.350      256.550
      109.530      300.440
      127.730      388.210
      130.000      398.330
! 
! Excluded regions (LowT  HighT)
        5.00       16.00
      130.00      170.00
! 
!
       1    !Number of refined parameters
!
!  Zero    Code    Sycos    Code   Sysin    Code  Lambda     Code MORE
 -0.0810   11.00  0.0000    0.00  0.0000    0.00 0.000000    0.00   0
!-------------------------------------------------------------------------------
!  Data for PHASE number:   1  ==> Current R_Bragg:     1.62
!-------------------------------------------------------------------------------
  K2TiF6                                                              
!
!Nat Dis Mom Pr1 Pr2 Pr3 Jbt Irf Isy Str Furth     ATZ   Nvk Npr More
   0   0   0 0.0 0.0 1.0   2   0   0   0   0        0.00   0   5   0
!
P -3 M 1                 <--Space group symbol
!  Scale       Shape1      Bov     Str1     Str2     Str3    Strain-Model
 0.10000E-01   0.2989   0.0000   0.0000   0.0000   0.0000       0

     0.00000    31.00     0.00     0.00     0.00     0.00

!      U        V         W          X         Y       GauSiz   LorSiz Size-Model
   0.05000  -0.02500   0.02500   0.00000   0.00000   0.00000   0.00000   0
     61.00     51.00     41.00    101.00      0.00      0.00      0.00
!     a          b         c        alpha      beta       gamma
   5.733000   5.733000   4.664600  90.000000  90.000000 120.000000
   71.00000   71.00000   81.00000    0.00000    0.00000   71.00000
!  Pref1  Pref2   Asy1    Asy2    Asy3     Asy4
 1.00000 0.00000 0.12870 0.02391 0.00000 0.00000
    0.00    0.00   91.00   21.00    0.00    0.00
As usual, only the zeropoint is refined for a few cycles, and then new cycles are made, refining all reasonable parameters taking account of the data quality (2-theta-max = 130° allows refining U and W and even X). Below is the final .sum file :
 
 

        ********************************************************
        ** PROGRAM FULLPROF.98 (Version 0.2  - Mar98-LLB JRC) **
        ********************************************************
           Rietveld, Profile Matching & Integrated Intensity
                Refinement of X-ray and/or Neutron Data


    Date: 14/03/2000  Time: 14:38:59.400                              

 => PCR file code: k2tif60
 => DAT file code: k2tif60
 => Title:   K2TiF6 P-3m1                                                       

 ==> CONDITIONS OF THIS RUN:

 => Global Refinement of X-ray powder diffraction data                          
    Bragg-Brentano or Debye-Scherrer geometry
 => The    5th default profile function was selected
 => Data supplied in free format 
 => Wavelengths:  1.54056 1.54439
 => Cos(Monochromator angle)=   0.7995
 => Absorption correction (muR-eff):   0.0000
 => Base of peaks: 2.0*HW*   20.00
 ==> Angular range, step and number of points:
     2Thmin:   5.0000  2Thmax: 130.0000  Step:   0.0200  No. of points:   6251
 => Pattern Matching (fixed scale) for phase: 1
 => Scor: 4.5072

 ==> RESULTS OF REFINEMENT:


 => No. of fitted parameters:   10


------------------------------------------------------------------------------
 => Phase No.  1   K2TiF6                                P -3 M 1            
------------------------------------------------------------------------------

 =>  No. of reflections:    226


 ==> PROFILE PARAMETERS:

 => Cell parameters      :
                              5.73305   0.00007
                              5.73305   0.00007
                              4.66459   0.00006
                             90.00000   0.00000
                             90.00000   0.00000
                            120.00000   0.00000
 
 => overall scale factor :    0.010000000   0.000000000
 => Eta(p-v) or m(p-vii) :    0.19519   0.01013
 => Overall tem. factor  :    0.00000   0.00000
 => Halfwidth parameters :    0.04474   0.00243
                             -0.02713   0.00234
                              0.02923   0.00057
 => Preferred orientation:    1.00000   0.00000
                              0.00000   0.00000
 => Asymmetry parameters :    0.14189   0.00289
                              0.03388   0.00082
                              0.00000   0.00000
                              0.00000   0.00000
 => X and y parameters   :    0.00799   0.00025
                              0.00000   0.00000
 => Strain parameters    :    0.00000   0.00000
                              0.00000   0.00000
                              0.00000   0.00000
 => Size   parameters    :    0.00000   0.00000
                              0.00000   0.00000

 ==> GLOBAL PARAMETERS:

 => Zero-point:  -0.0875  0.0008
 => Cos( theta)-shift parameter :   0.0000  0.0000
 => Sin(2theta)-shift parameter :   0.0000  0.0000

 ==> RELIABILITY FACTORS WITH ALL NON-EXCLUDED POINTS:

 => Cycle: 20 => MaxCycle: 20
 => N-P+C:  5689
 => Rp: 6.47     Rwp: 9.77     Rexp:    2.79 Chi2:  12.3      L.S. refinement
 => Conventional Rietveld R-factors ==>
 => Rp: 8.94     Rwp: 12.2     Rexp:    3.47 Chi2:  12.3    
 => Deviance: 0.704E+05     Dev*  :  12.37    
 => DW-Stat.:    0.2481     DW-exp:     1.9213
 => N-sigma of the GoF:  601.700

 ==> RELIABILITY FACTORS FOR POINTS WITH BRAGG CONTRIBUTIONS:

 => N-P+C:  5654
 => Rp: 6.48     Rwp: 9.78     Rexp:    2.78 Chi2:  12.4      L.S. refinement
 => Conventional Rietveld R-factors ==>
 => Rp: 8.93     Rwp: 12.2     Rexp:    3.46 Chi2:  12.4    
 => Deviance: 0.704E+05     Dev*  :  12.44    
 => DW-Stat.:    0.2482     DW-exp:     1.9211
 => N-sigma of the GoF:      603.664
 => Phase:  1
 => Bragg R-factor:  1.63       Vol:  132.775( 0.003)  Fract(%):    0.00( 0.00)
 => Rf-factor=0.971             ATZ:    0.000          Brindley:  1.0000

 => Run finished at:     Date: 14/03/2000  Time: 14:39:49.710
Rp=8.9% and Rwp= 12.2 is not too bad. People say that chi2 must be close to 1.0. This is mainly a view of statistician, but beleve me, first trust Rp and Rwp. Suppose you just divide your intensity by a factor 2. Then your Rexp value will increase a lot, and your chi2 will decrease since chi=Rwp/Rexp, (chi2=chi**2) and Rwp will not be very different from the current value excepted if the noise becomes really more important on that new scaled pattern.  Let us see the fit drawing :

A very nice fit, though the FWHM is large (between 0.15 and 0.37° 3-theta, due to the choice of a large 0.15° detector slit aperture on a Siemens D500, Bragg-Brentano, with graphite back monochromator). If there is a problem on that pattern, it will not be anisotropic broadening.

Let us now introduce the atoms with their coordinates in a new .pcr file, and refine. Below is the final .sum file :
 

 

        ********************************************************
        ** PROGRAM FULLPROF.98 (Version 0.2  - Mar98-LLB JRC) **
        ********************************************************
           Rietveld, Profile Matching & Integrated Intensity
                Refinement of X-ray and/or Neutron Data


    Date: 14/03/2000  Time: 15:40:33.300                              

 => PCR file code: k2tif6
 => DAT file code: k2tif6
 => Title:   K2TiF6 P-3m1                                                       

 ==> CONDITIONS OF THIS RUN:

 => Global Refinement of X-ray powder diffraction data                          
    Bragg-Brentano or Debye-Scherrer geometry
 => The    5th default profile function was selected
 => Data supplied in free format 
 => Wavelengths:  1.54056 1.54439
 => Cos(Monochromator angle)=   0.7995
 => Absorption correction (muR-eff):   0.0000
 => Base of peaks: 2.0*HW*   20.00
 ==> Angular range, step and number of points:
     2Thmin:   5.0000  2Thmax: 130.0000  Step:   0.0200  No. of points:   6251
 => Crystal Structure Refinement for phase: 1
 => Scor: 5.5089

 ==> RESULTS OF REFINEMENT:


 => No. of fitted parameters:   17


------------------------------------------------------------------------------
 => Phase No.  1   K2TiF6                                P -3 M 1            
------------------------------------------------------------------------------

 =>  No. of reflections:    228


 ==> ATOM PARAMETERS:

  Name    x     sx       y     sy       z      sz      B   sB  occ.  socc.

 K     0.33333(   0)  0.66667(   0)  0.70649(  72)  2.659( 95)  0.200(  0)
 TI    0.00000(   0)  0.00000(   0)  0.00000(   0)  0.710( 65)  0.100(  0)
 F     0.15706(  26)  0.84294(  26)  0.19363(  73)  0.871( 88)  0.600(  0)

 ==> PROFILE PARAMETERS:

 => Cell parameters      :
                              5.73158   0.00025
                              5.73158   0.00025
                              4.66423   0.00024
                             90.00000   0.00000
                             90.00000   0.00000
                            120.00000   0.00000
 
 => overall scale factor :    0.051430602   0.000433081
 => Eta(p-v) or m(p-vii) :    0.17984   0.02985
 => Overall tem. factor  :    0.00000   0.00000
 => Halfwidth parameters :    0.02734   0.00655
                             -0.00534   0.00645
                              0.02465   0.00158
 => Preferred orientation:    1.00000   0.00000
                              0.00000   0.00000
 => Asymmetry parameters :    0.08863   0.01435
                              0.03341   0.00254
                              0.00000   0.00000
                              0.00000   0.00000
 => X and y parameters   :    0.00874   0.00073
                              0.00000   0.00000
 => Strain parameters    :    0.00000   0.00000
                              0.00000   0.00000
                              0.00000   0.00000
 => Size   parameters    :    0.00000   0.00000
                              0.00000   0.00000

 ==> GLOBAL PARAMETERS:

 => Zero-point:  -0.1038  0.0037
 => Cos( theta)-shift parameter :   0.0000  0.0000
 => Sin(2theta)-shift parameter :   0.0000  0.0000

 ==> RELIABILITY FACTORS WITH ALL NON-EXCLUDED POINTS:

 => Cycle:  8 => MaxCycle:  8
 => N-P+C:  5682
 => Rp: 18.3     Rwp: 26.1     Rexp:    2.79 Chi2:  87.9      L.S. refinement
 => Conventional Rietveld R-factors ==>
 => Rp: 25.3     Rwp: 32.5     Rexp:    3.47 Chi2:  87.9    
 => Deviance: 0.910E+06     Dev*  :  160.1    
 => DW-Stat.:    0.0443     DW-exp:     1.9238
 => N-sigma of the GoF: 4632.408

 ==> RELIABILITY FACTORS FOR POINTS WITH BRAGG CONTRIBUTIONS:

 => N-P+C:  5640
 => Rp: 18.3     Rwp: 26.2     Rexp:    2.78 Chi2:  88.6      L.S. refinement
 => Conventional Rietveld R-factors ==>
 => Rp: 25.2     Rwp: 32.5     Rexp:    3.46 Chi2:  88.6    
 => Deviance: 0.910E+06     Dev*  :  161.3    
 => DW-Stat.:    0.0443     DW-exp:     1.9235
 => N-sigma of the GoF:     4649.726
 => Phase:  1
 => Bragg R-factor:  21.1       Vol:  132.697( 0.011)  Fract(%):    0.00( 0.00)
 => Rf-factor= 14.9             ATZ:    0.000          Brindley:  1.0000

 => Run finished at:     Date: 14/03/2000  Time: 15:41:03.400
This is not really satisfying. Very high Rp, Rwp and Bragg R factors are obtained. The fit drawing shows that a few reflections have big intensity problems :

We may look at their hkl Miller indices in the .out file :
 

 No.  Code     H   K   L  Mult    Hw     ETA/M   2theta/TOF     Icalc       Iobs      Sigma   Square-StrFactor

    1   1      0   1   0     3   0.156   0.336      17.855     1451.9     1301.4      4.542       65.4033
    2   1      1   0   0     3   0.156   0.336      17.855     1451.9     1301.4      4.542       65.4032
    3   1      0   0   1     2   0.157   0.346      19.011     3357.4     4114.7      7.361      257.4994
    4   1      0   1   1     6   0.158   0.409      26.196      831.8     1014.9      1.884       41.2810
    5   1      1   0   1     6   0.158   0.409      26.196    10548.2    12870.1      6.711      523.4990
    6   1      1   1   0     6   0.159   0.452      31.184     4316.4     3405.1      6.152      309.2498
    7   1      0   2   0     3   0.161   0.496      36.163      556.8      461.8      4.854      109.4788
    8   1      2   0   0     3   0.161   0.496      36.163      556.8      461.8      4.854      109.4788
    9   1      1   1   1    12   0.161   0.501      36.778      110.0       94.0      6.645        5.6073
   10   1      0   0   2     2   0.162   0.517      38.573     1323.3     5608.3     12.526      448.6279
   11   1      0   2   1     6   0.163   0.539      41.166     9975.3     9082.4      4.972     1298.2241
   12   1      2   0   1     6   0.163   0.539      41.166     3910.0     3560.0      3.113      508.8614
   13   1      0   1   2     6   0.164   0.554      42.807     2820.0     2798.4      6.477      399.6232
   14   1      1   0   2     6   0.164   0.554      42.807       11.0       10.9      0.405        1.5628
   15   1      1   2   0     6   0.167   0.603      48.482       32.8       12.1     11.956        6.0994
   16   1      2   1   0     6   0.167   0.603      48.482       32.8       12.1     11.956        6.0994
   17   1      1   1   2    12   0.168   0.620      50.407       56.4      120.7     12.862        5.7194
   18   1      1   2   1    12   0.169   0.639      52.533      329.5      309.3      2.812       36.5478
   19   1      2   1   1    12   0.169   0.639      52.533     1457.9     1368.7      5.915      161.7158
   20   1      0   2   2     6   0.170   0.651      53.903     2356.0     2428.4      5.562      552.8826
   21   1      2   0   2     6   0.170   0.651      53.903      842.7      868.6      3.327      197.7646
   22   1      0   3   0     3   0.171   0.665      55.491      303.6      338.6      5.345      151.7907
   23   1      3   0   0     3   0.171   0.665      55.491      303.6      338.6      5.345      151.7907
   24   1      0   3   1     6   0.174   0.697      59.204      129.3      289.6     12.359       37.1657
   25   1      3   0   1     6   0.174   0.697      59.204        5.4       12.0      2.518        1.5424
   26   1      0   0   3     2   0.175   0.699      59.397        3.1       21.7      4.221        2.6904
   27   1      0   1   3     6   0.177   0.726      62.554       54.1       31.1      5.371       17.4700
   28   1      1   0   3     6   0.177   0.726      62.554       35.5       20.4      4.352       11.4661
   29   1      1   2   2    12   0.178   0.735      63.598     1948.7     1560.6      6.110      325.5098
   30   1      2   1   2    12   0.178   0.735      63.598       51.3       41.1      0.992        8.5749

   31   1      2   2   0     6   0.180   0.748      65.037     2456.2     1986.5      5.927      859.0827
   32   1      1   3   0     6   0.183   0.774      68.045       68.1       52.6      3.953       26.0845
   33   1      3   1   0     6   0.183   0.774      68.045       68.1       52.6      3.953       26.0845
   34   1      2   2   1    12   0.183   0.778      68.439      384.6      301.0      3.873       74.4566
   35   1      1   1   3    12   0.184   0.779      68.618     1378.8     1372.2      5.740      268.3156
   36   1      0   3   2     6   0.185   0.788      69.614       57.1       42.3      6.343       22.8403
   37   1      3   0   2     6   0.185   0.788      69.614        1.3        1.0      0.955        0.5179
   38   1      1   3   1    12   0.187   0.803      71.378      738.8      774.4      5.870      154.9543
   39   1      3   1   1    12   0.187   0.803      71.378       81.8       85.7      1.953       17.1493
   40   1      0   2   3     6   0.187   0.805      71.553        3.8        4.3      0.380        1.5978
   41   1      2   0   3     6   0.187   0.805      71.553      841.3      961.8      5.660      354.5250
   42   1      0   4   0     3   0.194   0.850      76.739       12.3       10.4     10.265       11.6689
   43   1      4   0   0     3   0.194   0.850      76.739       12.3       10.4     10.265       11.6689
   44   1      2   2   2    12   0.196   0.863      78.238      305.7      282.3      8.363       75.0521
   45   1      0   4   1     6   0.198   0.878      79.931      180.2      205.7      3.164       91.3770
   46   1      4   0   1     6   0.198   0.878      79.931      724.0      826.8      6.343      367.2465
   47   1      1   2   3    12   0.199   0.880      80.099      102.6      106.9      2.328       26.1090
   48   1      2   1   3    12   0.199   0.880      80.099        2.4        2.5      0.357        0.6150
   49   1      1   3   2    12   0.200   0.888      81.043       20.8       21.6      1.328        5.3731
   50   1      3   1   2    12   0.200   0.888      81.043      506.7      527.6      6.560      131.0646
   51   1      0   0   4     2   0.203   0.902      82.689       66.4      471.9     17.226      105.9778
   52   1      2   3   0     6   0.207   0.924      85.130       83.3      117.4      4.804       45.9082
   53   1      3   2   0     6   0.207   0.924      85.130       83.3      117.4      4.804       45.9082
   54   1      0   1   4     6   0.208   0.926      85.464       17.9       36.7      1.654        9.9255
The biggest errors seem to come from the 00l reflections, always observed larger than calculated. This can also be seen by using some drawing program like DMPLOT :


 
 

We may thus suppose that, in spite of the precaution used for the sample preparation (vertical load of the sample holder), there could be some preferred orientation along the 00l direction.

Then we may test the March-Dollase option for a correction :
 

COMM   K2TiF6 P-3m1                                                       
! Files => DAT-file: k2tif6,  PCR-file: k2tif6
!Job Npr Nph Nba Nex Nsc Nor Dum Iwg Ilo Ias Res Ste Nre Cry Uni Cor
   0   5   1  20   2   0   1   1   0   0   1   0   0   0   0   0   0
!
!Ipr Ppl Ioc Mat Pcr Ls1 Ls2 Ls3 Syo Prf Ins Rpa Sym Hkl Fou Sho Ana
   0   0   1   0   1   0   0   0   1   1   0   1   0   0   2   0   0
!
! lambda1 Lambda2    Ratio   Bkpos    Wdt    Cthm     muR   AsyLim   Rpolarz
 1.540560 1.544390  0.5000 90.0000 20.0000  0.7995  0.0000   90.00    0.0000
!
!NCY Eps R_at R_an R_pr R_gl     Thmin       Step       Thmax    PSD    Sent0
  8 0.01 0.40 0.40 0.40 0.60      5.0000     0.0200   130.0000  0.000  0.000
!
!  2Theta/TOF   Background
        5.010     4104.130
        6.050     3431.700
        8.110     2481.030
       10.590     1889.760
       12.870     1356.450
       14.730     1059.970
       16.190      864.180
       19.910      614.380
       23.230      523.230
       29.010      421.960
       33.770      391.580
       47.430      364.580
       60.690      334.190
       74.970      303.810
       95.450      256.550
      100.010      256.550
      104.350      256.550
      109.530      300.440
      127.730      388.210
      130.010      398.330
! 
! Excluded regions (LowT  HighT)
        5.00       16.00
      130.00      170.00
! 
!
      18    !Number of refined parameters
!
!  Zero    Code    Sycos    Code   Sysin    Code  Lambda     Code MORE
 -0.1038   11.00  0.0000    0.00  0.0000    0.00 0.000000    0.00   0
!-------------------------------------------------------------------------------
!  Data for PHASE number:   1  ==> Current R_Bragg:    21.10
!-------------------------------------------------------------------------------
  K2TiF6                                                              
!
!Nat Dis Mom Pr1 Pr2 Pr3 Jbt Irf Isy Str Furth     ATZ   Nvk Npr More
   3   0   0 0.0 0.0 1.0   0   0   0   0   0        0.00   0   5   0
!
P -3 M 1                 <--Space group symbol
!Atom Typ       X        Y        Z     Biso      Occ     In Fin N_t  /Codes
K    K+1     0.33333  0.66667  0.70649  2.65903  0.20000   0   0   0
                0.00     0.00   111.00   121.00     0.00
TI   TI+4    0.00000  0.00000  0.00000  0.71041  0.10000   0   0   0
                0.00     0.00     0.00   131.00     0.00
F    F-1     0.15706  0.84294  0.19363  0.87125  0.60000   0   0   0
              141.00  -141.00   151.00   161.00     0.00
!  Scale       Shape1      Bov     Str1     Str2     Str3    Strain-Model
 0.51431E-01   0.1798   0.0000   0.0000   0.0000   0.0000       0
    21.00000    31.00     0.00     0.00     0.00     0.00
!      U        V         W          X         Y       GauSiz   LorSiz Size-Model
   0.02734  -0.00534   0.02465   0.00874   0.00000   0.00000   0.00000   0
     61.00     51.00     41.00    171.00      0.00      0.00      0.00
!     a          b         c        alpha      beta       gamma
   5.731583   5.731583   4.664235  90.000000  90.000000 120.000000
   71.00000   71.00000   81.00000    0.00000    0.00000   71.00000
!  Pref1  Pref2   Asy1    Asy2    Asy3     Asy4
 1.00000 0.00000 0.08863 0.03341 0.00000 0.00000
  181.00    0.00   91.00  101.00    0.00    0.00
After a few cycles, there is a strong improvement in the fit, as seen in the .sum file :
 
 

        *******************************************************
        *** PROGRAM FULLPROF (Version 3.3  - Aug97-LLB JRC) ***
        *******************************************************
           Rietveld, Profile Matching & Integrated Intensity
                Refinement of X-ray and/or Neutron Data


    Date: 03/14/00  Time: 17:15:37.97   

 => PCR file code: k2tif6
 => DAT file code: k2tif6
 => Title:   K2TiF6 P-3m1                                                       

 ==> CONDITIONS OF THIS RUN:

 => Global Refinement of X-ray powder diffraction data                          
    Bragg-Brentano or Debye-Scherrer geometry
 => The    5th default profile function was selected
 => Data supplied in free format 
 => Wavelengths:  1.54056 1.54439
 => Base of peaks: 2.0*HW*   20.00
 => Cos(Monochromator angle)=   0.7995
 => Absorption correction (muR-eff):   0.0000
 ==> Angular range, step and number of points:
     2Thmin:   5.0000  2Thmax: 130.0000  Step:   0.0200  No. of points:   6251
 => Crystal Structure Refinement for phase: 1
 => Scor: 5.3827

 ==> RESULTS OF REFINEMENT:


 => No. of fitted parameters:   18


------------------------------------------------------------------------------
 => Phase No.  1   K2TiF6                                P -3 M 1            
------------------------------------------------------------------------------

 =>  No. of reflections:    228


 ==> ATOM PARAMETERS:

  Name    x     sx       y     sy       z      sz      B   sB  occ.  socc.

 K     0.33333(   0)  0.66667(   0)  0.70355(  30)  1.777( 51)  0.200(  0)
 TI    0.00000(   0)  0.00000(   0)  0.00000(   0)  1.661( 60)  0.100(  0)
 F     0.15129(  20)  0.84871(  20)  0.22209(  32)  1.379( 57)  0.600(  0)

 ==> PROFILE PARAMETERS:

 => Cell parameters      :
                              5.73262   0.00016
                              5.73262   0.00016
                              4.66423   0.00013
                             90.00000   0.00000
                             90.00000   0.00000
                            120.00000   0.00000
 
 => Overall scale factor :    0.055830561   0.000288385
 => ETA(p-V) or M(P-VII) :    0.12428   0.01841
 => Overall Tem. factor  :    0.00000   0.00000
 => Halfwidth parameters :    0.01682   0.00359
                              0.00120   0.00377
                              0.02348   0.00097
 => Preferred orientation:    0.73477   0.00178
                              0.00000   0.00000
 => Asymmetry parameters :    0.10102   0.00899
                              0.03409   0.00159
                              0.00000   0.00000
                              0.00000   0.00000
 => X and Y parameters   :    0.00990   0.00046
                              0.00000   0.00000
 => Strain parameters    :    0.00000   0.00000
                              0.00000   0.00000
                              0.00000   0.00000
 => Size   parameters    :    0.00000   0.00000
                              0.00000   0.00000

 ==> GLOBAL PARAMETERS:

 => Zero-point:  -0.0977  0.0023
 => Cos( theta)-shift parameter :   0.0000  0.0000
 => Sin(2theta)-shift parameter :   0.0000  0.0000

 ==> RELIABILITY FACTORS WITH ALL NON-EXCLUDED POINTS:

 => Cycle:  8 => MaxCycle:  8
 => N-P+C:  5681
 => Rp: 12.8     Rwp: 16.7     Rexp:    2.79 Chi2:  35.8      L.S. refinement
 => Conventional Rietveld R-factors ==>
 => Rp: 17.7     Rwp: 20.8     Rexp:    3.47 Chi2:  35.8    
 => Deviance: 0.213E+06     Dev*  :  37.52    
 => DW-Stat.:    0.0922     DW-exp:     1.9241
 => N-sigma of the GoF: 1854.572

 ==> RELIABILITY FACTORS FOR POINTS WITH BRAGG CONTRIBUTIONS:

 => N-P+C:  5638
 => Rp: 12.8     Rwp: 16.7     Rexp:    2.78 Chi2:  36.1      L.S. refinement
 => Conventional Rietveld R-factors ==>
 => Rp: 17.6     Rwp: 20.8     Rexp:    3.46 Chi2:  36.1    
 => Deviance: 0.213E+06     Dev*  :  37.80    
 => DW-Stat.:    0.0922     DW-exp:     1.9239
 => N-sigma of the GoF:     1861.713
 => Phase:  1
 => Bragg R-factor:  12.8       Vol:     132.745   Fract(%):     0.00
 => Rf-factor= 10.4             ATZ:       0.000   Brindley:   1.0000
However, a Bragg R factor of 12.8 % is still unacceptable, and the Rp value of 17.6 % is too much far from the value obtained without the structure contraint (< 9%).

The preferred orientation parameter is equal to 0.73 (instead of 1.00 if no preferred orientation occured). This is huge !

We may consider that it will not be possible to treat correctly such data, and record a new pattern more carefully. Possibly by the technique of dusting the sample through a sieve on the sample holder, or using some spray dry technique. This is the best thing to do, anyway, before to waste time by trying anisotropic thermal parameters, or disorder, or anything else.

This shows the limits of a preferred orientation correction by the March Dollase option in a Rietveld program.

Final plot as seen by the DMPLOT program. Some people may found that fit acceptable, but it is certainly not :


 
 


STRATEGY - SUMMARY - CHECKLIST

We hope that you have now an idea of the strategies commonly selected for performing a Rietveld refinement (with structure constraint - note that the strategy is different when there is only a cell contraint like in the Pawley or Le Bail methods) :