Slawsonite
Benna P, Nestola F, Ballaran T B, Balic-Zunic T, Lundegaard L F, Bruno E
American Mineralogist 92 (2007) 1190-1199
The high-pressure structural configurations of Ca0.2Sr0.8Al2Si2O8 feldspar:
The I-1-I2/c and I2/c-P2_1/c phase transitions
Sample: P = 4.4 GPa
Locality: synthetic
_database_code_amcsd 0004409
8.209 12.780 14.009 90 115.27 90 I2/c
atom     x      y     z occ Uiso
Ca   .2672 -.0005 .0671  .2 .029
Sr   .2672 -.0005 .0671  .8 .029
Si10 .9993  .1743 .1071     .037
Al1z .9964  .1785 .6169     .033
Al20 .6870  .1198 .1703     .035
Si2z .6794  .1125 .6721     .036
OA1  .0019  .1267 .9978     .038
OA2  .5857  .9950 .1473     .046
OB0  .8185  .1205 .1025     .042
OBz  .7976  .1255 .6075     .044
OC0  .0012  .3004 .1177     .047
OCz  .0051  .3135 .6311     .056
OD0  .1864  .1248 .1975     .047
ODz  .1932  .1207 .7052     .048