Cervandonite-(Ce) Diffraction data computed using the structure from the paper listed below, along with the cell parameters refined from single crystal data of R110070 Demartin F, Gramaccioli C M, Graeser S The Canadian Mineralogist 46 (2008) 423-430 The crystal structure of cervandonite-(Ce), an interesting example of As3+ - Si diadochy Locality: Alpine fissures at Pizzo Cervandone, Scherbadung, Central Alps Note: Chemistry from original description of the mineral. _database_code_amcsd 0006185 CELL PARAMETERS: 6.4920 6.4920 18.5030 90.000 90.000 120.000 SPACE GROUP: R3m ATOM X Y Z OCCUPANCY ISO(B) Ce 0.00000 0.00000 0.00000 0.440 1.603 Nd 0.00000 0.00000 0.00000 0.220 1.603 La 0.00000 0.00000 0.00000 0.210 1.603 Th 0.00000 0.00000 0.00000 0.060 1.603 Y 0.00000 0.00000 0.00000 0.030 1.603 U 0.00000 0.00000 0.00000 0.020 1.603 Ca 0.00000 0.00000 0.00000 0.020 1.603 Fe 0.16820 0.33650 -0.16610 0.417 2.440 Fe 0.16820 0.33650 -0.16610 0.140 2.440 Ti 0.16820 0.33650 -0.16610 0.313 2.440 Al 0.16820 0.33650 -0.16610 0.127 2.440 Sn 0.16820 0.33650 -0.16610 0.003 2.440 As 0.33333 0.66667 0.34700 0.580 1.445 As 0.33333 0.66667 -0.01560 0.580 2.456 Si 0.33333 0.66667 0.36980 0.420 2.298 Si 0.33333 0.66667 0.19280 0.420 1.484 Si 0.33333 0.66667 0.14240 0.420 1.484 Si 0.33333 0.66667 -0.03550 0.420 2.298 O 0.00000 0.00000 -0.14040 1.000 5.606 O 0.00000 0.00000 0.14000 1.000 5.685 O 0.20240 0.40480 0.16730 1.000 2.298 O 0.06080 0.53040 0.39260 1.000 2.756 O 0.19260 0.38530 -0.06380 1.000 1.871 O 0.33333 0.66667 0.28240 1.000 3.000 O 0.33333 0.66667 0.05320 1.000 1.816 X-RAY WAVELENGTH: 1.541838 BOUNDS ON TWO THETA: 5.0 90.0 LIMITS IMPOSED ON THE INDICES ARE: +/- 5 +/- 5 +/- 16 MAX. ABS. INTENSITY / VOLUME**2: 44.01614988 The INTENSITY cut off value is 1.00 2-THETA INTENSITY D-SPACING H K L 14.36 7.76 6.1677 0 0 3 16.48 37.48 5.3794 1 0 1 18.47 2.63 4.8046 0 1 2 24.93 18.29 3.5721 1 0 4 27.48 76.47 3.2460 1 1 0 28.95 37.76 3.0838 0 0 6 31.14 100.00 2.8725 1 1 3 32.21 9.57 2.7792 0 2 1 33.31 28.99 2.6897 2 0 2 37.44 8.42 2.4023 0 2 4 37.60 20.63 2.3921 1 0 7 40.34 28.67 2.2357 1 1 6 42.25 1.60 2.1390 0 1 8 42.84 15.77 2.1111 2 1 1 43.71 2.30 2.0711 1 2 2 47.06 1.64 1.9310 2 1 4 47.20 1.59 1.9257 0 2 7 48.58 10.40 1.8741 3 0 0 49.46 2.43 1.8428 1 2 5 50.93 15.67 1.7931 0 3 3 50.93 7.69 1.7931 3 0 3 51.14 8.54 1.7861 2 0 8 52.03 3.57 1.7576 1 0 10 52.70 14.35 1.7368 1 1 9 55.48 8.30 1.6562 2 1 7 56.72 27.70 1.6230 2 2 0 57.55 2.99 1.6015 3 0 6 57.55 5.82 1.6015 0 3 6 58.83 2.21 1.5696 2 2 3 59.49 1.69 1.5538 1 3 1 59.84 11.49 1.5456 0 2 10 60.00 2.24 1.5419 0 0 12 62.90 1.20 1.4776 1 3 4 64.93 14.41 1.4362 2 2 6 67.07 1.87 1.3954 2 1 10 67.39 2.44 1.3896 0 4 2 67.64 3.06 1.3850 0 3 9 67.64 3.76 1.3850 3 0 9 67.94 3.36 1.3798 1 0 13 69.95 1.67 1.3448 4 0 4 70.06 4.53 1.3430 1 3 7 74.76 1.53 1.2698 0 2 13 76.70 1.86 1.2424 3 2 4 77.86 4.75 1.2269 4 1 0 79.68 3.30 1.2033 1 4 3 79.68 4.92 1.2033 4 1 3 79.85 1.07 1.2012 0 4 8 80.56 1.76 1.1924 1 3 10 81.37 5.10 1.1826 2 1 13 83.37 2.47 1.1592 3 2 7 83.91 2.05 1.1531 1 1 15 85.10 1.72 1.1400 1 4 6 85.10 2.51 1.1400 4 1 6 87.07 2.37 1.1192 4 0 10 87.20 2.93 1.1179 2 2 12 ================================================================================ XPOW Copyright 1993 Bob Downs, Ranjini Swaminathan and Kurt Bartelmehs For reference, see Downs et al. (1993) American Mineralogist 78, 1104-1107.