UPPW6 AUTOX Dear Armel! A quick trying of orthorhombic symmetry under the former assumptions about the accuracy and assuming that the volume <=2000 gave me the following results. ************************************************************************ * Starting Powder Indexing Mode= Full powder indexing * Phase 1 Minimizer = 0.000000 symmetry= orthorhombic HKL_max/min_ph1 8 0 8 0 8 V_max= 2000 N_ref= 728 Par_max_ph1 20.00 20.00 20.00 90.00 90.00 90.00 Par_min_ph1 2.00 2.00 2.00 90.00 90.00 90.00 * Powder Indexing Fitting performed. N of trials = 8192 Chi2/df = 0.34 Dif(A) = 0.00229 Phase No 1 Vol= 1379.42 A = 8.9193 +- 0.0060 B = 8.3873 +- 0.0044 C = 18.4393 +- 0.0163 alpha = 90.00 +- 0.00 beta = 90.00 +- 0.00 gamma = 90.00 +- 0.00 Powder Indexing N h k l phase d_exp d_fit Dif. chi2 1 0 1 1 7.64160 7.63459 -0.00701 2.0 2 1 0 2 6.41220 6.41045 -0.00175 0.1 3 1 1 1 5.80230 5.79999 -0.00231 0.2 4 2 0 0 4.46150 4.45964 -0.00186 0.1 5 0 2 0 4.19080 4.19363 0.00283 0.3 6 1 0 4 4.09910 4.09521 -0.00389 0.6 7 2 0 2 4.01140 4.01464 0.00324 0.4 8 0 2 2 3.81440 3.81730 0.00290 0.3 9 1 2 2 3.50520 3.50940 0.00420 0.7 10 2 1 3 3.31310 3.31559 0.00249 0.2 11 2 0 4 3.20450 3.20523 0.00073 0.0 12 1 1 5 3.15560 3.15734 0.00174 0.1 13 0 2 4 3.09980 3.10208 0.00228 0.2 14 2 2 2 2.89840 2.89999 0.00159 0.1 15 3 1 1 2.77150 2.77044 -0.00106 0.0 16 2 1 5 2.69130 2.69168 0.00038 0.0 17 3 0 4 2.49800 2.49853 0.00053 0.0 18 2 3 1 2.34940 2.34946 0.00006 0.0 19 0 0 8 2.30200 2.30492 0.00292 0.3 20 2 3 3 2.20640 2.21031 0.00391 0.6 21 1 3 5 2.15950 2.16151 0.00201 0.2 22 3 3 0 2.03810 2.03671 -0.00139 0.1 23 1 4 2 1.99140 1.99291 0.00151 0.1 24 3 3 3 1.93100 1.93333 0.00233 0.2 Average d - d_calc (A) = 0.00229 Max d - d_calc (A) = 0.00701 Average exp_error (A) = 0.00500 N(d-visible) / N(d_exp) = 91 / 24 Phase 1 real hkl range: ( 0, 3), ( 0, 4), ( 0, 8) Criterion = 6.523 phase chi2/N(d) = 0.34