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 = 1.80 GPa
_database_code_amcsd 0008034
7.7937 7.7937 4.9696 90 90 90 P-42_1m
atom     x     y     z Biso B(1,1) B(2,2) B(3,3) B(1,2) B(1,3) B(2,3)
Ca   .3331 .1669 .5053 1.26  .0055  .0055  .0110  .0021  .0010  .0010
Mg       0     0     0  .83  .0024  .0024  .0136      0      0      0
Si   .1404 .3596 .9346  .78  .0032  .0032  .0080 -.0001 -.0001 -.0001
O1      .5     0 .1838  1.5  .0072  .0072  .0092 -.0042      0      0
O2   .1404 .3596 .2558  1.5  .0059  .0059  .0152  .0021 -.0013 -.0013
O3   .0813 .1853 .7819  1.3  .0081  .0032  .0105 -.0012  .0024 -.0022