COL  ICSD Collection Code 67687
 DATE Recorded Jan 19, 1994; updated Jun 26, 1998
 NAME Dicalcium aluminium alumosilicate
 MINR Gehlenite - synthetic, glas annealed at 1250 C for 2 d
 MINR Melilite group
 FORM Ca2 Al (Al Si O7)
      = Al2 Ca2 O7 Si
 TITL Neutron Diffraction Study of the Akermanite-Gehlenite Solid 
      Solution Series
 REF  Physics and Chemistry of Minerals (Germany)
      PCMID 19 (1992) 185-195
 AUT  Swainson I P, Dove˙M˙T, Schmahl˙W˙W, Putnis˙A
 CELL a=7.685 b=7.685 c=5.064 ŕ=90.0 á=90.0 ç=90.0
      V=299.1 Z=2
 SGR  P -4 21 m     (113) - tetragonal
 CLAS -42m  (Hermann-Mauguin) - D2d (Schoenflies)
 PRS  tP24
 ANX  A2B3X7
 PARM Atom__No OxStat  Wyck ---X--- ---Y--- ---Z---  -SOF-
      Ca     1  2.000    4e  0.3389  0.1611  0.5104
      Al     1  3.000    2a  0.      0.      0.
      Si     1  4.000    4e  0.1434  0.3566  0.954     0.5
      Al     2  3.000    4e  0.1434  0.3566  0.954     0.5
      O      1 -2.000    2c  1/2     0.      0.1765
      O      2 -2.000    4e  0.1427  0.3573  0.2835
      O      3 -2.000    8f  0.0876  0.1678  0.8078
 WYCK f e3 c a
˙
 TF   Atom   B(1,1)  B(2,2)  B(3,3)  B(1,2)  B(1,3)  B(2,3)
      Ca 1    1.9200  1.9200  0.5900  0.6500 -0.1300 -0.1300
      Al 1    0.6800  0.6800  0.7600  0.0000  0.0000  0.0000
      Si 1    0.5000  0.5000  0.2000 -0.0800  0.0700  0.0700
      Al 2    0.5000  0.5000  0.2000 -0.0800  0.0700  0.0700
      O  1    1.2200  1.2200  0.4200 -0.3200  0.0000  0.0000
      O  2    1.3600  1.3600  0.6700  0.0000  0.2600  0.2600
      O  3    1.5600  0.8700  0.7700 -0.2700  0.3700 -0.0200
 REM  TEM 300
 REM  NDP (neutron diffraction from a powder)
 REM  M PDF 35-755
 RVAL 0.059
 TEST At least one temperature factor is implausible or meaningless but 
      agrees with the value given in the paper. (Code 52)