Penkvilksite
Merlino S, Pasero M, Artioli G, Khomyakov A P
American Mineralogist 79 (1994) 1185-1193
Penkvilksite, a new kind of silicate structure: OD character, X-ray
single-crystal (1M), and powder Rietveld (2O) refinements of two MDO polytypes
Note: polytype 2O
_database_code_amcsd 0001688
16.3721 8.7492 7.4020 90 90 90 Pnca
atom     x     y      z occ  Uiso
Ti       0    .5      0  .9 .0310
Zr       0    .5      0  .1 .0310
Si1  .0825 .1613  .1247     .0312
Si2  .1567 .4399  .2603     .0161
Na   .1023 .6911  .6220      .063
O1   .1599 .2612  .2006      .025
O2   .0501 .0372  .2695      .028
O3   .0074 .2704  .0633      .025
O4   .1162 .0507 -.0389      .033
O5   .1115 .5394  .1052      .021
O6     .25    .5  .2705      .016
OW   .1954 .6844 -.1548      .049
H1    .173  .586  -.108       .10
H2    .242  .650  -.232       .14