data_global _chemical_name_mineral 'Diopside' loop_ _publ_author_name 'Thompson R M' 'Downs R T' _journal_name_full 'American Mineralogist' _journal_volume 93 _journal_year 2008 _journal_page_first 177 _journal_page_last 186 _publ_section_title ; The crystal structure of diopside at pressure to 10 GPa Sample: P = 10.16 GPa ; _database_code_amcsd 0004504 _chemical_compound_source 'DeKalb, New York' _chemical_formula_sum 'Mg Ca Si2 O6' _cell_length_a 9.5164 _cell_length_b 8.6449 _cell_length_c 5.1246 _cell_angle_alpha 90 _cell_angle_beta 105.033 _cell_angle_gamma 90 _cell_volume 407.164 _exptl_crystal_density_diffrn 3.533 _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 _atom_site_U_iso_or_equiv Mg 0.00000 0.91075 0.25000 0.00557 Ca 0.00000 0.30587 0.25000 0.00849 Si 0.28610 0.09554 0.22718 0.00595 O1 0.11538 0.08832 0.14178 0.00722 O2 0.35921 0.25714 0.32226 0.00861 O3 0.35409 0.02340 0.98725 0.00849