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 Rich63
Atomic parameters from ICSD
_database_code_amcsd 0001614
10.0149 18.0099 5.2862 90 104.954 90 C2/m
atom     x     y     z occ Biso
O1   .1125 .0882 .2203       .8
O2   .1137 .1701 .7246       .8
F    .1001     0 .7177       .8
O3    .355 .2482 .7925       .8
O4   .3367 .1295  .092      1.1
O5   .3367 .1167 .5938      1.1
O6   .3329     0 .3141      1.2
Si1  .2787 .0852 .3036       .4
Si2  .2832 .1702 .8066 .96   .4
Ti   .2832 .1702 .8066 .04   .4
Mg1      0   .09    .5       .6
Mg2      0 .1796     0       .6
Mg3      0     0     0       .6
Na       0 .2765    .5  .5   .9
Ca       0 .2765    .5  .5   .9
K    .0233    .5 .0518  .5  2.3