Tugtupite
Antao S M, Hassan I, Parise J B
American Mineralogist 89 (2004) 492-497
Tugtupite: High-temperature structures obtained from in situ synchrotron
diffraction and Rietveld refinements
T = 773 C
_database_code_amcsd 0003461
8.69349 8.69349 8.9064 90 90 90 I-4
atom     x     y     z  Uiso
Al       0    .5   .75 .0195
Be       0    .5   .25  .014
Si   .0118 .2541 .4949 .0195
O1   .1496 .1383 .4492 .0246
O2   .3434 .0320 .6524 .0246
O3   .4337 .1457 .1399 .0246
Na   .1622 .1980 .1832 .0615
Cl       0     0     0 .0789