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 = 4.93 GPa, natural orthopyroxene _database_code_amcsd 0008023 18.051 8.6683 5.1244 90 90 90 Pbca atom x y z occ Biso MgM1 .378 .6558 .858 .01 MgM2 .3762 .4815 .3522 .66 .03 FeM2 .3762 .4815 .3522 .24 .03 CaM2 .3762 .4815 .3522 .012 .03 AlM2 .3762 .4815 .3522 .08 .03 SiTA .270 .3441 .040 .97 .11 AlTA .270 .3441 .040 .03 .11 SiTB .472 .3389 .8033 .97 .11 AlTB .472 .3389 .8033 .03 .11 O1a .179 .339 .021 .27 O2a .304 .509 .040 .27 O3a .302 .228 .819 .27 O1b .562 .337 .811 .27 O2b .430 .487 .690 .27 O3b .448 .191 .613 .27