Akermanite
      Kusaka K, Hagiya K, Ohmasa M, Okano Y, Mukai M, Iishi K, Haga N
      Physics and Chemistry of Minerals 28 (2001) 150-166
      Determination of structures of Ca2CoSi2O7, Ca2MgSi2O7, and Ca2(Mg.55Fe.45)Si2O7
      in incommensurate and normal phases and observation of diffuse streaks at high temperature
      Sample: T = 513 K
      Melilite group
      _database_code_amcsd 0008523

      CELL PARAMETERS:    7.8509   7.8509   5.0127   90.000   90.000   90.000
      SPACE GROUP: P-42_1m   
      X-RAY WAVELENGTH:     1.541838
      Cell Volume:    308.966
      Density (g/cm3):      2.930
      MAX. ABS. INTENSITY / VOLUME**2:      22.19527450    
      RIR:      2.467
      RIR based on corundum from Acta Crystallographica A38 (1982) 733-739
               2-THETA      INTENSITY    D-SPACING   H   K   L   Multiplicity
                15.96          9.76        5.5514    1   1   0         4
                17.69          1.77        5.0127    0   0   1         2
                21.03          7.46        4.2250    1   0   1         8
                22.65          3.19        3.9255    2   0   0         4
                23.92         11.25        3.7204    1   1   1         4
                25.37          4.24        3.5110    2   1   0         8
                28.89         23.20        3.0906    2   0   1         8
                31.10        100.00        2.8758    2   1   1         8
                32.25          3.83        2.7757    2   2   0         4
                35.83          1.64        2.5064    0   0   2         2
                36.18         16.18        2.4827    3   1   0         8
                37.02          5.32        2.4283    2   2   1         4
                37.67          6.46        2.3876    1   0   2         8
                38.82          6.64        2.3199    3   0   1         8
                39.45          2.71        2.2843    1   1   2         4
                40.55          1.58        2.2248    3   1   1         8
                44.41         12.90        2.0399    2   1   2         8
                45.41          2.34        1.9972    3   2   1         8
                46.26          5.64        1.9627    4   0   0         4
                47.77          6.62        1.9041    4   1   0         8
                48.97          4.12        1.8602    2   2   2         4
                49.24          9.81        1.8505    3   3   0         4
                51.33          9.11        1.7800    4   1   1         8
                51.83         19.35        1.7638    3   1   2         8
                52.10          6.14        1.7555    4   2   0         8
                52.73          3.26        1.7360    3   3   1         4
                54.95          1.13        1.6709    0   0   3         2
                55.94          2.42        1.6438    3   2   2         8
                57.61          1.74        1.6000    1   1   3         4
                60.19          1.47        1.5374    2   0   3         8
                61.46          4.23        1.5088    2   1   3         8
                62.38          1.29        1.4887    3   3   2         4
                63.17          2.70        1.4718    5   1   1         8
                65.17          4.62        1.4315    2   2   3         4
                66.38          2.60        1.4083    3   0   3         8
                66.83          8.91        1.3999    5   2   1         8
                67.49          2.88        1.3879    4   4   0         4
                70.39          1.73        1.3375    4   4   1         4
                70.81          1.39        1.3306    4   3   2         8
                72.20          3.11        1.3085    6   0   0         4
                73.35          1.09        1.2907    6   1   0         8
                75.43          1.21        1.2602    5   2   2         8
                75.73          4.31        1.2559    4   1   3         8
                75.93          1.12        1.2532    0   0   4         2
                76.16          1.02        1.2499    6   1   1         8
                76.87          2.17        1.2401    3   3   3         4
                79.55          1.94        1.2049    6   2   1         8
                80.68          2.28        1.1910    5   4   1         8
                81.08          1.21        1.1861    5   3   2         8
                83.31          1.99        1.1599    6   0   2         8
                84.71          1.47        1.1442    4   3   3         8
                84.90          1.02        1.1422    2   2   4         4
                85.82          2.38        1.1323    5   1   3         8
                86.01          1.26        1.1303    3   0   4         8
                87.12          1.15        1.1187    3   1   4         8
                87.74          1.08        1.1124    6   2   2         8
                89.14          1.10        1.0985    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.