Richterite
Della Ventura G, Robert J-L, Beny J-M, Raudsepp M, Hawthorne F C
American Mineralogist 78 (1993) 980-987
The OH-F substitution in Ti-rich potassium richterite: Rietveld structure
refinement and FTIR and micro-Raman spectroscopic studies of synthetic
amphiboles in the system K2O-Na2O-CaO-MgO-SiO2-TiO2-H2O-HF
Sample Rich61
Atomic parameters from ICSD
_database_code_amcsd 0001612
10.0262 18.0194 5.2871 90 104.874 90 C2/m
atom     x     y     z occ Biso
O1   .1118 .0888  .213       .8
O2   .1153   .17 .7255       .8
OH    .104     0 .7163  .4   .8
F     .104     0 .7163  .6   .8
O4   .3546 .2472  .792       .8
O5   .3383 .1281 .0957      1.1
O6   .3383  .116 .5918      1.1
O7   .3326     0 .3105      1.2
Si1  .2772 .0856 .2999       .4
Si2  .2844 .1706 .8118  .9   .4
Ti   .2844 .1706 .8118  .1   .4
Mg1      0   .09    .5       .6
Mg2      0 .1789     0       .6
Mg3      0     0     0       .6
Na       0 .2762    .5  .5   .9
Ca       0 .2762    .5  .5   .9
K    .0263    .5 .0578  .5  2.3