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 = 700 C pyroxene ; _database_code_amcsd 0000342 _chemical_formula_sum 'Si2 Mg Ca O6' _cell_length_a 9.799 _cell_length_b 9.029 _cell_length_c 5.274 _cell_angle_alpha 90 _cell_angle_beta 106 _cell_angle_gamma 90 _cell_volume 448.542 _exptl_crystal_density_diffrn 3.207 _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 0.28610 0.09250 0.22940 Mg1 0.00000 0.90690 0.25000 Ca2 0.00000 0.30050 0.25000 O1 0.11640 0.08640 0.14230 O2 0.36040 0.24770 0.31490 O3 0.34950 0.01570 0.99710 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 0.01151 0.01441 0.01710 -0.00138 0.00419 -0.00074 Mg1 0.01650 0.01875 0.01772 0.00000 0.00404 0.00000 Ca2 0.03263 0.01933 0.02388 0.00000 -0.00082 0.00000 O1 0.01286 0.02309 0.02215 -0.00013 0.00513 0.00019 O2 0.02841 0.01867 0.02668 -0.00788 0.00622 -0.00206 O3 0.01807 0.02647 0.02180 -0.00069 0.00772 -0.00675