Eucryptite
Pillars W W, Peacor D R
American Mineralogist 58 (1973) 681-690
The crystal structure of beta eucryptite as a function of temperature
T = 647 C
_database_code_amcsd 0000381
5.251 5.251 11.189 90 90 120 P6_422
atom     x     y     z Biso
Si     1/2     0     0 1.11
Al     1/2     0   1/2 1.12
Li       0     0     0  7.6
O    .2111 .4045 .7458  2.8