Ca2(Mg.55Fe.45)Si2O7 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 = 297 K Melilite group _database_code_amcsd 0008524 7.8679 7.8679 5.0144 90 90 90 P-42_1m atom x y z occ Biso Mg 0 0 0 .55 .98 Fe 0 0 0 .45 .98 Ca .3307 .1693 .5061 1.91 Si .1384 .3616 .9383 .89 O1 0 .5 .825 3.4 O2 .1390 .361 .2570 2.20 O3 .0795 .1898 .7891 3.0