Bertrandite Diffraction data computed using the structute from the paper listed below, along with the cell parameters refined from single crystal data of R060800 Hazen R M, Au A Y Physics and Chemistry of Minerals 13 (1986) 69-78 High-pressure crystal chemistry of phenakite (Be2SiO4) and bertrandite (Be4Si2O7(OH)2) Sample: P = 41 kbar Note: y-coordinate of O3 altered CELL PARAMETERS: 8.7260 15.0100 4.5230 90.000 90.000 90.000 SPACE GROUP: Cmc2_1 ATOM X Y Z OCCUPANCY ISO(B) Be 0.17230 0.05450 0.13600 1.000 0.800 Be 0.32970 0.22330 0.06500 1.000 0.500 Si 0.32700 0.11280 0.64990 1.000 0.450 O 0.29560 0.12330 0.00000 1.000 0.800 O 0.20480 0.04430 0.50340 1.000 0.800 O 0.29900 0.20860 0.48460 1.000 1.100 O 0.00000 0.57960 0.58800 1.000 0.700 OH 0.00000 0.76280 0.05330 1.000 0.500 OH 0.00000 0.09470 0.07620 1.000 0.600 X-RAY WAVELENGTH: 1.541838 BOUNDS ON TWO THETA: 5.0 90.0 LIMITS IMPOSED ON THE INDICES ARE: +/- 8 +/- 13 +/- 4 MAX. ABS. INTENSITY / VOLUME**2: 6.200921217 The INTENSITY cut off value is 1.00 2-THETA INTENSITY D-SPACING H K L 11.73 24.08 7.5439 1 1 0 11.79 1.40 7.5050 0 2 0 20.35 99.68 4.3630 2 0 0 20.46 30.14 4.3405 1 3 0 22.93 11.28 3.8792 1 1 1 22.96 43.59 3.8739 0 2 1 23.71 21.27 3.7525 0 4 0 28.50 100.00 3.1317 1 3 1 30.87 10.52 2.8968 2 2 1 30.96 1.83 2.8880 0 4 1 31.33 10.85 2.8555 3 1 0 31.44 4.69 2.8450 2 4 0 31.52 4.13 2.8387 1 5 0 35.71 63.49 2.5146 3 3 0 35.90 23.68 2.5017 0 6 0 37.24 7.83 2.4146 3 1 1 37.34 1.19 2.4082 2 4 1 37.40 1.27 2.4044 1 5 1 39.86 52.49 2.2615 0 0 2 41.07 27.60 2.1978 3 3 1 41.24 24.46 2.1891 0 6 1 41.39 5.73 2.1815 4 0 0 41.61 1.34 2.1702 2 6 0 41.69 2.02 2.1663 1 1 2 41.71 2.16 2.1653 0 2 2 43.31 4.56 2.0890 3 5 0 45.16 4.89 2.0078 2 0 2 45.21 1.29 2.0056 1 3 2 46.41 14.28 1.9566 2 6 1 46.91 8.11 1.9369 0 4 2 47.85 1.21 1.9008 4 2 1 47.97 1.59 1.8965 3 5 1 48.10 3.27 1.8915 1 7 1 48.52 1.81 1.8763 0 8 0 51.55 3.54 1.7729 3 1 2 51.63 1.99 1.7703 2 4 2 51.68 2.43 1.7688 1 5 2 52.83 1.52 1.7331 0 8 1 54.58 11.26 1.6815 3 3 2 54.71 7.64 1.6776 0 6 2 55.79 8.54 1.6478 5 3 0 55.92 1.10 1.6442 4 6 0 56.15 1.79 1.6381 1 9 0 56.88 1.21 1.6187 5 1 1 57.12 4.10 1.6126 3 7 1 58.81 4.38 1.5701 4 0 2 58.99 1.40 1.5659 2 6 2 59.72 6.67 1.5483 5 3 1 59.85 10.02 1.5452 4 6 1 60.07 4.79 1.5402 1 9 1 60.32 5.85 1.5345 3 5 2 61.46 1.05 1.5088 5 5 0 62.86 1.46 1.4784 1 1 3 62.87 2.72 1.4781 0 2 3 64.02 8.32 1.4543 6 0 0 64.39 19.34 1.4468 3 9 0 64.54 1.38 1.4440 0 8 2 65.54 6.44 1.4242 1 3 3 66.83 1.25 1.4000 2 2 3 68.44 1.01 1.3709 2 8 2 68.97 3.25 1.3615 6 2 1 69.29 1.38 1.3561 6 4 0 70.65 1.97 1.3332 3 1 3 70.74 2.61 1.3318 5 3 2 70.86 1.03 1.3299 4 6 2 72.96 1.49 1.2967 5 7 1 73.20 11.57 1.2931 3 3 3 73.31 10.27 1.2913 0 6 3 75.64 2.80 1.2573 6 6 0 75.79 1.53 1.2551 5 5 2 76.10 2.16 1.2508 0 12 0 77.01 8.44 1.2382 2 6 3 78.13 5.39 1.2232 6 0 2 78.48 9.03 1.2187 3 9 2 79.05 2.83 1.2114 6 6 1 79.49 3.61 1.2057 5 9 0 79.76 5.44 1.2024 2 12 0 80.62 2.02 1.1917 3 11 1 82.56 6.84 1.1685 7 3 1 82.86 3.68 1.1651 5 9 1 83.04 2.45 1.1630 6 4 2 83.12 2.35 1.1620 2 12 1 85.32 1.05 1.1376 5 1 3 85.52 1.67 1.1355 3 7 3 87.75 6.13 1.1123 5 3 3 89.10 2.60 1.0989 6 6 2 89.55 1.08 1.0946 2 0 4 ================================================================================ XPOW Copyright 1993 Bob Downs, Ranjini Swaminathan and Kurt Bartelmehs For reference, see Downs et al. (1993) American Mineralogist 78, 1104-1107.