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 = 1000 C pyroxene ; _database_code_amcsd 0000344 _chemical_formula_sum 'Si2 Mg Ca O6' _cell_length_a 9.822 _cell_length_b 9.081 _cell_length_c 5.285 _cell_angle_alpha 90 _cell_angle_beta 105.98 _cell_angle_gamma 90 _cell_volume 453.173 _exptl_crystal_density_diffrn 3.174 _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 0.28590 0.09240 0.22920 Mg1 0.00000 0.90630 0.25000 Ca2 0.00000 0.30010 0.25000 O1 0.11640 0.08640 0.14230 O2 0.36070 0.24640 0.31430 O3 0.34870 0.01460 -0.00240 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 0.01522 0.01938 0.01764 -0.00130 0.00447 -0.00091 Mg1 0.02489 0.02561 0.02000 0.00000 0.00462 0.00000 Ca2 0.04643 0.02624 0.02731 0.00000 -0.00253 0.00000 O1 0.01748 0.03092 0.02469 -0.00030 0.00428 0.00047 O2 0.03875 0.02561 0.03297 -0.01047 0.00676 -0.00402 O3 0.02380 0.03497 0.02290 0.00126 0.00790 -0.00879