Akermanite Yang H, Hazen R M, Downs R T, Finger L W Physics and Chemistry of Minerals 24 (1997) 510-519 Structural change associated with the incommensurate-normal phase transition in akermanite, Ca2MgSi2O7, at high pressure Sample: P = 1.37 GPa _database_code_amcsd 0008033 CELL PARAMETERS: 7.8046 7.8046 4.9772 90.000 90.000 90.000 SPACE GROUP: P-42_1m X-RAY WAVELENGTH: 1.541838 Cell Volume: 303.170 Density (g/cm3): 2.986 MAX. ABS. INTENSITY / VOLUME**2: 22.53725077 RIR: 2.458 RIR based on corundum from Acta Crystallographica A38 (1982) 733-739 2-THETA INTENSITY D-SPACING H K L Multiplicity 16.06 9.53 5.5187 1 1 0 4 17.82 1.36 4.9772 0 0 1 2 21.17 7.38 4.1965 1 0 1 8 22.79 2.89 3.9023 2 0 0 4 24.08 11.29 3.6961 1 1 1 4 25.52 3.95 3.4903 2 1 0 8 29.08 22.55 3.0710 2 0 1 8 31.30 100.00 2.8577 2 1 1 8 32.45 3.81 2.7593 2 2 0 4 36.09 1.57 2.4886 0 0 2 2 36.40 16.37 2.4680 3 1 0 8 37.26 5.57 2.4133 2 2 1 4 37.95 6.10 2.3710 1 0 2 8 39.07 6.90 2.3056 3 0 1 8 39.73 2.55 2.2686 1 1 2 4 40.81 1.60 2.2111 3 1 1 8 44.72 12.91 2.0263 2 1 2 8 45.71 2.54 1.9850 3 2 1 8 46.55 5.91 1.9511 4 0 0 4 48.07 6.35 1.8929 4 1 0 8 49.31 4.02 1.8480 2 2 2 4 49.55 10.13 1.8396 3 3 0 4 51.66 9.31 1.7693 4 1 1 8 52.20 19.73 1.7524 3 1 2 8 52.43 6.04 1.7452 4 2 0 8 53.08 3.23 1.7255 3 3 1 4 55.38 1.02 1.6591 0 0 3 2 56.33 2.22 1.6332 3 2 2 8 58.05 1.73 1.5888 1 1 3 4 60.65 1.37 1.5268 2 0 3 8 61.93 4.54 1.4984 2 1 3 8 62.82 1.31 1.4793 3 3 2 4 63.60 2.53 1.4630 5 1 1 8 65.67 4.63 1.4219 2 2 3 4 66.89 2.72 1.3988 3 0 3 8 67.29 9.16 1.3915 5 2 1 8 67.94 2.95 1.3797 4 4 0 4 70.88 1.60 1.3295 4 4 1 4 71.32 1.39 1.3223 4 3 2 8 72.69 3.24 1.3008 6 0 0 4 75.99 1.36 1.2524 5 2 2 8 76.32 4.15 1.2477 4 1 3 8 76.57 1.20 1.2443 0 0 4 2 76.70 1.08 1.2424 6 1 1 8 77.47 2.16 1.2320 3 3 3 4 80.13 1.83 1.1978 6 2 1 8 81.26 2.37 1.1839 5 4 1 8 81.69 1.18 1.1788 5 3 2 8 83.94 1.98 1.1528 6 0 2 8 85.39 1.41 1.1369 4 3 3 8 86.51 2.37 1.1250 5 1 3 8 86.75 1.21 1.1225 3 0 4 8 87.87 1.11 1.1111 3 1 4 8 88.42 1.07 1.1056 6 2 2 8 89.87 1.23 1.0915 5 2 3 8 ================================================================================ XPOW Copyright 1993 Bob Downs, Ranjini Swaminathan and Kurt Bartelmehs For reference, see Downs et al. (1993) American Mineralogist 78, 1104-1107.