Fluoro-eckermannite
Oberti R, Hawthorne F C, Camara F, Raudsepp M
American Mineralogist 84 (1999) 102-111
Unusual M3+ cations in synthetic amphiboles with nominal fluoro-eckermannite
composition: Deviations from stoichiometry and structural effects of the
cummingtonite component
Sample: Ti, Na.85Na1.02Mg.98Mg4.83Ti.17Si8O22F2
_database_code_amcsd 0002057
9.691 17.930 5.284 90 102.98 90 C2/m
atom       x     y     z occ Biso
Si(1)  .2840 .0848 .2851      .60
Si(2)  .2916 .1707 .7907      .59
Mg(1)      0 .0887    .5      .59
Ti(2)      0 .1796     0 .09  .67
Mg(2)      0 .1796     0 .91  .67
Mg(3)      0     0     0      .50
Na(4)      0 .2655    .5 .45 1.96
Mg(4)      0 .2655    .5 .55 1.96
NaA        0    .5     0 .27 2.72
NaA(m) .0462    .5 .1034 .33 2.38
O1     .1137 .0849 .2136      .55
O2     .1199 .1692 .7230      .82
F3     .1037     0 .7080      .78
O4     .3678 .2489 .7848     1.70
O5     .3505 .1283 .0718     1.48
O6     .3467 .1183 .5720     1.76
O7     .3456     0 .2812     1.07