Ilvaite Diffraction data computed using the structure from the paper listed below, along with the cell parameters refined from the powder pattern of R050040 Ghose S, Sen Gupta P K, Schlemper E O American Mineralogist 70 (1985) 1248-1252 Electron ordering in ilvaite, a mixed-valence iron silicate: crystal structure refinement at 138 K Sample: T = 138 K CELL PARAMETERS: 12.9980 8.7860 5.8409 90.000 90.407 90.000 SPACE GROUP: P2_1/a ATOM X Y Z OCCUPANCY ISO(B) Fe 0.89001 0.05004 0.00852 1.000 0.320 Fe 0.88996 0.05218 0.49051 1.000 0.307 Fe 0.94134 0.74089 0.24923 1.000 0.307 Ca 0.81261 0.37020 0.75256 1.000 0.316 Si 0.95954 0.36916 0.24920 1.000 0.233 Si 0.67914 0.22764 0.25180 1.000 0.231 O 0.00900 0.02940 0.73790 1.000 0.510 O 0.93690 0.27220 0.01590 1.000 0.350 O 0.93540 0.27280 0.48290 1.000 0.340 O 0.77740 0.11020 0.25530 1.000 0.330 O 0.67060 0.32890 0.01790 1.000 0.370 O 0.67030 0.33180 0.48300 1.000 0.360 O 0.58480 0.10080 0.25240 1.000 0.330 O 0.60180 0.02640 0.75190 1.000 0.430 O 0.79800 0.10960 0.74410 1.000 0.360 H 0.74100 0.09800 0.74300 1.000 3.200 X-RAY WAVELENGTH: 1.541838 BOUNDS ON TWO THETA: 5.0 90.0 LIMITS IMPOSED ON THE INDICES ARE: +/- 11 +/- 8 +/- 5 MAX. ABS. INTENSITY / VOLUME**2: 11.21587893 The INTENSITY cut off value is 1.00 2-THETA INTENSITY D-SPACING H K L 12.16 100.00 7.2790 1 1 0 13.63 32.37 6.4988 2 0 0 18.24 10.32 4.8640 0 1 1 19.45 8.46 4.5644 -1 1 1 19.52 6.25 4.5467 1 1 1 21.35 6.69 4.1617 1 2 0 22.77 3.69 3.9052 -2 1 1 22.89 23.82 3.8858 3 1 0 22.90 3.09 3.8831 2 1 1 26.27 4.26 3.3930 -1 2 1 26.32 2.78 3.3857 1 2 1 27.45 25.82 3.2494 4 0 0 27.49 3.38 3.2448 -3 1 1 27.65 3.40 3.2258 3 1 1 28.94 11.79 3.0847 3 2 0 30.61 7.85 2.9204 0 0 2 31.31 39.44 2.8570 1 3 0 31.41 54.28 2.8482 -4 0 1 31.60 52.00 2.8310 4 0 1 32.76 11.15 2.7334 -3 2 1 32.90 11.12 2.7220 3 2 1 33.00 54.13 2.7141 -1 1 2 33.10 53.48 2.7067 1 1 2 33.56 74.82 2.6701 2 3 0 34.25 1.58 2.6180 0 3 1 34.33 17.93 2.6124 4 2 0 34.94 3.78 2.5680 -1 3 1 34.98 3.52 2.5649 1 3 1 35.12 13.15 2.5554 -2 1 2 35.29 12.34 2.5430 2 1 2 36.03 10.72 2.4927 5 1 0 36.96 21.82 2.4320 0 2 2 36.98 19.20 2.4310 -2 3 1 37.06 19.43 2.4257 2 3 1 37.64 15.16 2.3898 -4 2 1 37.80 17.07 2.3797 4 2 1 38.44 17.05 2.3417 -3 1 2 38.69 18.33 2.3274 3 1 2 40.19 1.92 2.2439 -3 3 1 40.31 1.37 2.2375 3 3 1 41.09 1.34 2.1965 0 4 0 41.42 19.66 2.1798 -4 0 2 41.69 2.35 2.1663 6 0 0 41.70 21.52 2.1658 1 4 0 41.73 18.76 2.1644 4 0 2 42.52 5.55 2.1261 -3 2 2 42.74 30.10 2.1156 -4 1 2 42.75 5.82 2.1154 3 2 2 43.04 28.54 2.1016 4 1 2 43.49 14.53 2.0809 2 4 0 46.28 5.59 1.9616 -2 4 1 46.35 15.21 1.9591 3 4 0 46.35 5.36 1.9588 2 4 1 46.51 7.87 1.9526 -4 2 2 46.72 1.57 1.9441 5 3 0 46.76 1.85 1.9429 6 2 0 46.79 7.89 1.9416 4 2 2 47.81 15.71 1.9024 -5 1 2 47.85 3.98 1.9008 0 1 3 48.16 16.05 1.8896 5 1 2 49.32 2.23 1.8476 -5 3 1 49.34 1.87 1.8471 -6 2 1 49.49 1.94 1.8417 5 3 1 49.54 2.22 1.8401 6 2 1 50.13 2.33 1.8197 4 4 0 50.22 2.09 1.8167 7 1 0 51.80 1.36 1.7650 -1 2 3 52.10 2.10 1.7554 0 4 2 52.41 1.45 1.7458 -6 0 2 52.43 1.64 1.7451 -3 1 3 52.58 7.09 1.7406 -1 4 2 52.62 1.04 1.7393 -4 4 1 52.64 6.84 1.7386 1 4 2 52.72 1.71 1.7362 3 1 3 52.79 1.43 1.7340 6 0 2 53.58 20.04 1.7103 7 2 0 54.06 1.53 1.6963 2 5 0 54.53 1.21 1.6827 0 5 1 54.71 1.02 1.6778 5 4 0 54.79 6.50 1.6753 -4 0 3 54.93 7.06 1.6716 -6 3 1 55.11 7.16 1.6664 6 3 1 55.17 5.46 1.6649 4 0 3 55.98 1.00 1.6427 3 2 3 56.46 7.71 1.6298 -2 5 1 56.48 8.11 1.6294 -3 4 2 56.52 7.43 1.6282 2 5 1 56.65 2.81 1.6247 8 0 0 56.66 7.40 1.6245 3 4 2 56.74 1.47 1.6224 -6 2 2 56.74 11.37 1.6223 -5 3 2 57.05 11.07 1.6144 5 3 2 57.11 1.57 1.6129 6 2 2 57.22 1.68 1.6100 -1 3 3 57.31 2.15 1.6077 1 3 3 57.70 1.82 1.5976 8 1 0 58.60 4.91 1.5753 -2 3 3 58.78 4.70 1.5709 2 3 3 59.01 2.95 1.5654 -4 2 3 59.36 3.30 1.5568 4 2 3 59.92 1.37 1.5438 -8 1 1 59.98 2.71 1.5424 6 4 0 60.15 1.13 1.5383 8 1 1 60.78 20.56 1.5238 8 2 0 61.87 21.41 1.4996 -6 3 2 62.22 21.66 1.4921 6 3 2 63.36 27.07 1.4680 -2 5 2 63.47 26.78 1.4656 2 5 2 63.53 2.36 1.4643 0 6 0 63.74 31.63 1.4602 0 0 4 63.98 5.04 1.4551 1 6 0 65.50 8.10 1.4251 9 1 0 65.55 5.93 1.4241 -8 0 2 65.87 4.81 1.4180 7 4 0 66.00 5.80 1.4155 8 0 2 67.52 4.33 1.3872 3 6 0 67.96 1.01 1.3794 -5 3 3 68.37 1.15 1.3721 5 3 3 68.60 1.53 1.3680 -4 5 2 68.79 11.67 1.3647 6 5 0 68.82 1.30 1.3642 4 5 2 69.62 1.45 1.3504 -3 6 1 69.71 1.32 1.3490 3 6 1 70.52 1.18 1.3354 -4 0 4 70.84 1.46 1.3302 -6 5 1 70.95 1.32 1.3284 4 0 4 71.00 1.40 1.3276 6 5 1 72.45 1.11 1.3045 0 5 3 72.63 2.44 1.3017 -6 3 3 72.68 2.58 1.3010 -1 3 4 72.78 2.72 1.2994 1 3 4 73.11 2.31 1.2944 6 3 3 73.68 2.01 1.2858 10 1 0 73.88 6.15 1.2827 -2 3 4 74.02 2.44 1.2807 -8 3 2 74.06 3.94 1.2801 -2 5 3 74.10 6.57 1.2796 2 3 4 74.22 3.84 1.2778 2 5 3 74.22 1.52 1.2777 -4 2 4 74.44 2.33 1.2745 8 3 2 74.65 1.49 1.2715 4 2 4 75.19 1.66 1.2637 -5 1 4 75.71 1.36 1.2562 5 1 4 76.35 1.48 1.2474 -5 6 1 76.42 6.07 1.2464 10 2 0 76.48 1.57 1.2455 5 6 1 77.45 1.17 1.2324 2 7 0 78.91 1.68 1.2132 6 6 0 79.05 1.68 1.2114 -1 4 4 79.15 2.00 1.2101 1 4 4 80.22 1.29 1.1965 -2 4 4 80.43 1.12 1.1940 2 4 4 80.52 1.91 1.1929 8 5 0 81.02 3.53 1.1868 -9 3 2 81.48 3.53 1.1812 9 3 2 82.21 1.92 1.1726 -3 4 4 82.36 2.05 1.1708 4 7 0 82.52 2.04 1.1690 3 4 4 82.81 1.82 1.1657 -10 3 1 83.06 1.62 1.1627 10 3 1 85.94 1.14 1.1310 -3 6 3 86.17 1.26 1.1286 3 6 3 87.01 1.53 1.1199 -6 5 3 87.47 1.54 1.1152 6 5 3 87.57 3.61 1.1141 -7 2 4 88.28 3.55 1.1069 7 2 4 88.69 2.10 1.1030 -10 3 2 88.81 2.96 1.1018 -4 0 5 89.20 2.11 1.0980 10 3 2 89.32 2.61 1.0968 4 0 5 ================================================================================ XPOW Copyright 1993 Bob Downs, Ranjini Swaminathan and Kurt Bartelmehs For reference, see Downs et al. (1993) American Mineralogist 78, 1104-1107.