Ilvaite
Ghose S, Tsukimura K, Hatch D M
Physics and Chemistry of Minerals 16 (1989) 483-496
Phase transitions in ilvaite, a mixed-valence iron silicate
II. A single-crystal X-ray diffraction study and Landau theory of the
monoclinic to orthorhombic phase transition induced by charge delocalization
Sample: T = 360 K
_database_code_amcsd 0007456
13.0497 8.8291 5.8652 90 90.029 90 P2_1/a
atom        x      y      z  Uiso U(1,1) U(2,2) U(3,3) U(1,2) U(1,3) U(2,3)
FeAo   .89027 .05067 .00689 .0095  .0109  .0087  .0090 -.0001 -.0008  .0009
FeAm   .89017 .05094 .49302 .0092  .0107  .0085  .0086 -.0003  .0004 -.0005
FeB    .94047 .73949 .24974 .0102  .0128  .0087  .0093 -.0007 -.0003 -.0002
Ca     .81298 .37052 .75032 .0102  .0112  .0082  .0114  .0010 -.0006  .0000
Si1    .95956 .36835 .24987 .0069  .0089  .0068  .0052  .0000 -.0002 -.0004
Si2    .67949 .22708 .25028 .0072  .0092  .0071  .0055  .0003 -.0004  .0003
O1     .00982 .02881 .74902 .0137  .0146  .0116  .0149  .0004  .0000 -.0003
O2o    .93645 .27245 .01641 .0093  .0124  .0102  .0053 -.0013  .0006 -.0014
O2m    .93615 .27195 .48393 .0090  .0121  .0102  .0049 -.0005 -.0008  .0015
O3     .77704 .10967 .25046 .0096  .0102  .0092  .0097  .0019 -.0005 -.0006
O4o    .67093 .32970 .01853 .0096  .0117  .0091  .0082  .0003  .0000  .0013
O4m    .67097 .32959 .48165 .0104  .0127  .0110  .0076  .0008 -.0001 -.0026
O5     .58527 .10120 .25028 .0094  .0105  .0071  .0109  .0017  .0004 -.0006
O6     .60194 .02447 .74977 .0128  .0129  .0102  .0154 -.0028 -.0003 -.0004
OH7    .79794 .10926 .74962 .0097  .0113  .0090  .0090  .0014  .0007  .0010