Braunite
Miletich R, Allan D R, Angel R J
Physics and Chemistry of Minerals 25 (1998) 183-192
Structural control of polyhedral compression in synthetic braunite,
Mn2+Mn3+6O8SiO4
Sample: P = 2.66 GPa
_database_code_amcsd 0008126
9.3786 9.3786 18.6234 90 90 90 *I4_1/acd
0 -.25 .125
atom      x      y      z Biso B(1,1) B(2,2) B(3,3)  B(1,2) B(1,3) B(2,3)
Mn1       0    .25    1/8 1.18 .00352 .00352 .00077 -.00101      0      0
Mn2       0      0      0  .90 .00241 .00255 .00069 -.00043 .00009 .00004
Mn3     .25 .21589      0  .87 .00237 .00228 .00071       0 .00012      0
Mn4  .23263 .48263    1/8  .84 .00226 .00226 .00066 -.00016 .00016 .00016
Si        0    .25    3/8  .94 .00251 .00251 .00077       0      0      0
O1   .14971 .85484 .94579  .92
O2   .14422 .07201 .05673 1.04
O3   .07885 .13328 .92554 1.10