data_global _chemical_name_mineral 'Diopside' loop_ _publ_author_name 'Levien L' 'Prewitt C T' _journal_name_full 'American Mineralogist' _journal_volume 66 _journal_year 1981 _journal_page_first 315 _journal_page_last 323 _publ_section_title ; High-pressure structural study of diopside P = 35.2 kbar pyroxene ; _database_code_amcsd 0000813 _chemical_formula_sum 'Si2 Mg Ca O6' _cell_length_a 9.656 _cell_length_b 8.813 _cell_length_c 5.2026 _cell_angle_alpha 90 _cell_angle_beta 105.49 _cell_angle_gamma 90 _cell_volume 426.651 _exptl_crystal_density_diffrn 3.371 _symmetry_space_group_name_H-M 'C 1 2/c 1' loop_ _space_group_symop_operation_xyz 'x,y,z' '1/2+x,1/2+y,z' 'x,-y,1/2+z' '1/2+x,1/2-y,1/2+z' '-x,y,1/2-z' '1/2-x,1/2+y,1/2-z' '-x,-y,-z' '1/2-x,1/2-y,-z' loop_ _atom_site_label _atom_site_fract_x _atom_site_fract_y _atom_site_fract_z Si 0.28643 0.09420 0.22820 Mg1 0.00000 0.90900 0.25000 Ca2 0.00000 0.30333 0.25000 O1 0.11530 0.08790 0.14220 O2 0.36080 0.25290 0.31960 O3 0.35250 0.02020 0.99070 loop_ _atom_site_aniso_label _atom_site_aniso_U_11 _atom_site_aniso_U_22 _atom_site_aniso_U_33 _atom_site_aniso_U_12 _atom_site_aniso_U_13 _atom_site_aniso_U_23 Si 0.00351 0.00512 0.00369 -0.00046 0.00095 -0.00020 Mg1 0.00395 0.00472 0.00357 0.00000 0.00095 0.00000 Ca2 0.00877 0.00630 0.00560 0.00000 0.00024 0.00000 O1 0.00614 0.00630 0.00522 0.00000 0.00095 0.00000 O2 0.00658 0.00630 0.00739 -0.00208 0.00142 -0.00090 O3 0.00702 0.00787 0.00522 0.00000 0.00260 -0.00201