Pyroxene-ideal
Thompson R M, Downs R T
American Mineralogist 89 (2004) 614-628
Model pyroxenes II: Structural variation as a function of tetrahedral rotation
model spodumene after Arlt and Angel (2003)
with O3-O3-O3 angle = 189.9 and model oxygen radius = 1.263
_database_code_amcsd 0003489
9.572 8.715 5.032 90 112.1 90 C2/c
atom     x      y      z
Al       0  11/12    1/4
Li       0    .25    1/4
Si   .3081   1/12  .3041
O1   .1337   1/12  .1792
O2   .3663    .25  .3208
O3   .3663 -.0124  .1082