data_global _chemical_name_mineral 'Diopside' loop_ _publ_author_name 'Cameron M' 'Sueno S' 'Prewitt C T' 'Papike J J' _journal_name_full 'American Mineralogist' _journal_volume 58 _journal_year 1973 _journal_page_first 594 _journal_page_last 618 _publ_section_title ; High-temperature crystal chemistry of acmite, diopside, hedenbergite, jadeite, spodumene, and ureyite T = 24 C pyroxene ; _database_code_amcsd 0000340 _chemical_formula_sum 'Si2 Mg Ca O6' _cell_length_a 9.745 _cell_length_b 8.899 _cell_length_c 5.251 _cell_angle_alpha 90 _cell_angle_beta 105.63 _cell_angle_gamma 90 _cell_volume 438.532 _exptl_crystal_density_diffrn 3.280 _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 0.28620 0.09330 0.22930 Mg1 0.00000 0.90820 0.25000 Ca2 0.00000 0.30150 0.25000 O1 0.11560 0.08730 0.14220 O2 0.36110 0.25000 0.31800 O3 0.35050 0.01760 0.99530 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 0.00245 0.00285 0.00332 -0.00013 0.00060 -0.00023 Mg1 0.00335 0.00301 0.00319 0.00000 0.00022 0.00000 Ca2 0.00803 0.00461 0.00549 0.00000 -0.00079 0.00000 O1 0.00272 0.00501 0.00460 0.00025 0.00026 0.00039 O2 0.00674 0.00381 0.00644 -0.00233 0.00070 -0.00021 O3 0.00410 0.00614 0.00442 0.00000 0.00125 -0.00157