Sillimanite
Winter J K, Ghose S
American Mineralogist 64 (1979) 573-586
Thermal expansion and high-temperature crystal chemistry of the Al2SiO5 polymorphs
T = 400 deg C
_database_code_amcsd 0000724
7.4932 7.7035 5.7872 90 90 90 Pbnm
atom     x     y     z B(1,1) B(2,2) B(3,3) B(1,2) B(1,3) B(2,3)
Al1      0     0     0 0.0024 0.0036 0.0061 -.0001 -.0002 -.0001
Al2  .1415 .3455   .25 0.0026 0.0038 0.0067 -.0001      0      0
Si   .1528 .3407   .75 0.0024 0.0032 0.0062 -.0004      0      0
O1   .3598 .4099   .75 0.0024 0.0051 0.0081 -.0010      0      0
O2   .3567 .4351   .25 0.0027 0.0053 0.0076 -.0012      0      0
O3   .4771 .0012   .75 0.0068 0.0070 0.0154 -.0036      0      0
O4   .1249 .2241 .5146 0.0051 0.0039 0.0065 -.0012 -.0002 -.0002