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 = 869 C
_database_code_amcsd 0003463
8.70359 8.70359 8.9147 90 90 90 I-4
atom     x     y     z  Uiso
Al       0    .5   .75 .0205
Be       0    .5   .25  .014
Si   .0117 .2540 .4948 .0205
O1   .1492 .1388 .4502 .0266
O2   .3432 .0316 .6526 .0266
O3   .4351 .1458 .1399 .0266
Na   .1628 .1984 .1834 .0656
Cl       0     0     0 .0874