Enstatite Hugh-Jones D A, Chopelas A, Angel R J Physics and Chemistry of Minerals 24 (1997) 301-310 Tetrahedral compression in (Mg,Fe)SiO3 orthopyroxenes Sample: P = 4.03 GPa, natural orthopyroxene _database_code_amcsd 0008022 18.077 8.6907 5.1349 90 90 90 Pbca atom x y z occ Biso MgM1 .377 .6550 .860 .16 MgM2 .378 .4818 .3525 .66 .16 FeM2 .378 .4818 .3525 .24 .16 CaM2 .378 .4818 .3525 .012 .16 AlM2 .378 .4818 .3525 .08 .16 SiTA .271 .3431 .040 .97 .04 AlTA .271 .3431 .040 .03 .04 SiTB .473 .3385 .804 .97 .04 AlTB .473 .3385 .804 .03 .04 O1a .181 .338 .031 .27 O2a .310 .508 .039 .27 O3a .305 .227 .819 .27 O1b .562 .336 .809 .27 O2b .433 .486 .691 .27 O3b .444 .192 .609 .27