Oxy-dravite
Gatta G D, Bosi F, McIntyre G J, Skogby H
Mineralogical Magazine 78 (2014) 681-692
First accurate location of two proton sites in tourmaline: A single-crystal
neutron diffraction study of oxy-dravite
Note: H1 site off the three-fold axis
Locality: Osarara, Narok District, Kenya
_database_code_amcsd 0020484
15.9272 15.9272 7.2001 90 90 120 R3m
atom      x      y      z   occ   Uiso U(1,1) U(2,2) U(3,3) U(1,2) U(1,3) U(2,3)
NaX       0      0  .2324  .873  .0107  .0087  .0087  .0148  .0043      0      0
AlY  .12267 .06134 .63585  .529 .00519  .0052  .0033  .0078  .0026 -.0028 -.0014
MgY  .12267 .06134 .63585  .271 .00519  .0052  .0033  .0078  .0026 -.0028 -.0014
FeY  .12267 .06134 .63585    .2 .00519  .0052  .0033  .0078  .0026 -.0028 -.0014
AlZ  .29768 .26140 .61077  .825 .00266  .0023  .0021  .0033  .0009 -.0004 -.0001
MgZ  .29768 .26140 .61077  .175 .00266  .0023  .0021  .0033  .0009 -.0004 -.0001
B    .10989 .21979 .45431       .00353  .0024  .0023  .0059  .0011  .0004  .0007
SiT  .19162 .18987 .00078       .00295  .0028  .0022  .0039  .0012 -.0005 -.0004
O1        0      0 .77118       .00933  .0110  .0110  .0059  .0055      0      0
O2   .06069 .12138 .48769       .00765  .0096  .0032  .0080  .0016  .0004  .0008
O3   .26136 .13068 .50988 1.013 .01077  .0191  .0105  .0055  .0095  .0009  .0004
O4   .09382 .18763 .07268       .00622  .0041  .0088  .0072  .0044 -.0007 -.0013
O5   .18437 .09219 .09380       .00599  .0081  .0042  .0070  .0041  .0006  .0003
O6   .19459 .18441 .77775       .00578  .0072  .0076  .0045  .0052 -.0006 -.0008
O7   .28541 .28486 .07822       .00587  .0050  .0036  .0070  .0006 -.0024 -.0005
O8   .20919 .27007 .43990       .00684  .0033  .0060  .0112  .0024  .0006  .0011
H3   .25766 .12883 .37526  .954  .0252  .0451  .0288  .0072  .0226  .0008  .0004
H1    .0194  .0097  .9043  .101   .014