Forsterite Hazen R M American Mineralogist 61 (1976) 1280-1293 Effects of temperature and pressure on the crystal structure of forsterite T = 23 C P = 50 kb olivine _database_code_amcsd 0000552 4.712 9.97 5.955 90 90 90 Pbnm atom x y z Biso Si .428 .101 .25 .7 Mg1 0 0 0 .2 Mg2 .993 .283 .25 .6 O1 .776 .103 .25 .1 O2 .228 .440 .25 .4 O3 .281 .153 .032 .6