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 = 463 K
Melilite group
_database_code_amcsd 0008522
7.8470 7.8470 5.0097 90 90 90 P-42_1m
atom     x     y     z Biso
Mg       0     0     0  .75
Ca   .3320  .168 .5058 1.34
Si   .1398 .3602 .9337  .62
O1       0    .5  .819  1.6
O2   .1403 .3597 .2551  1.6
O3   .0829 .1864 .7874 1.51