Piemontite
Nagashima M, Akasaka M
American Mineralogist 89 (2004) 1119-1129
An X-ray Rietveld study of piemontite on the join
Ca2Al3Si3O12(OH) - Ca2Mn3+3Si3O12(OH) formed by hydrothermal synthesis
Sample: q = 0.75, p = 0.75, Synthesis at P=200 MPa, T=500 C
_database_code_amcsd 0003587
8.8530 5.6596 10.1501 90 115.511 90 P2_1/m
atom     x    y    z occ
Ca1   .756  3/4 .153
Ca2   .603  3/4 .424
AlM1     0    0    0 .92
MnM1     0    0    0 .08
AlM2     0    0  1/2 .98
MnM2     0    0  1/2 .02
AlM3  .295  .25 .223 .35
MnM3  .295  .25 .223 .65
Si1   .337  3/4 .045
Si2   .681  .25 .275
Si3   .186  3/4 .320
O1    .235 .989 .034
O2    .305 .980 .355
O3    .794 .017 .343
O4    .064  .25 .132
O5    .042  3/4 .148
O6    .068  3/4 .406
O7    .517  3/4 .181
O8    .522  .25 .309
O9    .621  .25 .095
OH10  .080  .25 .424