data_global _chemical_name_mineral 'Diopside' loop_ _publ_author_name 'Raudsepp M' 'Hawthorne F C' 'Turnock A C' _journal_name_full 'American Mineralogist' _journal_volume 75 _journal_year 1990 _journal_page_first 1274 _journal_page_last 1281 _publ_section_title ; Crystal chemistry of synthetic pyroxenes on the join CaNiSi2O6-CaMgSi2O6 (diopside): A Rietveld refinement study sample Ni50, CaNi.45Mg.55Si2O6 ; _database_code_amcsd 0001335 _chemical_formula_sum '(Ni.45 Mg.55) Ca Si2 O6' _cell_length_a 9.7390 _cell_length_b 8.9094 _cell_length_c 5.2375 _cell_angle_alpha 90 _cell_angle_beta 105.848 _cell_angle_gamma 90 _cell_volume 437.177 _exptl_crystal_density_diffrn 3.525 _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_occupancy _atom_site_U_iso_or_equiv Ni1 0.00000 0.90790 0.25000 0.45000 0.00469 Mg1 0.00000 0.90790 0.25000 0.55000 0.00469 Ca2 0.00000 0.29940 0.25000 1.00000 0.00804 Si 0.28650 0.09340 0.22830 1.00000 0.00442 O1 0.11500 0.08740 0.14390 1.00000 0.00646 O2 0.36100 0.25190 0.31900 1.00000 0.00823 O3 0.35140 0.01780 0.99610 1.00000 0.00709