I agree, that refining the cell parameters using the full powder pattern is
more precise with respect to the minor error in d(obs) that you make.
Now my problem as a synthetic inorganic chemist is most often this: I do
have patterns of rather poor quality (only 1-2 sec integration time per
step) thus the signal-to-noise-ratio is most often not suitable for a
Rietveld-refinement (10-20; unless I do have very well crystallized
samples).
In fact, for 90% of my XRD patterns, it would be sufficient to determine
the lattice constants (and space group) directly from the routine xrd
patterns.
Do you think, the methods are developped enough to treat this noisy stuff?
Would be much easier for me ;-).
Greetings from Bordeaux
Carsten
PS: I forgot to mention the usual range of my routine patterns: 5-80 °2Q.
Usually, I will find about 40-60 reflections within this range.
Carsten Schinzer ---------------------------------------
Institut de Chimie de la Matiere Condensee de Bordeaux
87, Avenue du Docteur A. Schweitzer
F-33608 PESSAC
fon +33 556 84 2650 (poste 7397) fax +33 556 84 2761
http://www.icmcb.u-bordeaux.fr/~schinzer
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