data_global _chemical_name_mineral 'Diopside' loop_ _publ_author_name 'Comodi P' 'Princivalle F' 'Tirone M' 'Zanazzi P F' _journal_name_full 'European Journal of Mineralogy' _journal_volume 7 _journal_year 1995 _journal_page_first 141 _journal_page_last 149 _publ_section_title ; Comparative compressibility of clinopyroxenes from mantle nodules Sample: PC135 at room conditions ; _database_code_amcsd 0006580 _chemical_formula_sum 'Mg.957 Al.25 Fe.112 Ti.008 Cr.044 Ca.645 Na.094 Mn.002 Si1.888 O6' _cell_length_a 9.678 _cell_length_b 8.836 _cell_length_c 5.257 _cell_angle_alpha 90 _cell_angle_beta 106.9 _cell_angle_gamma 90 _cell_volume 430.137 _exptl_crystal_density_diffrn 3.337 _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 MgM1 0.00000 0.90650 0.25000 0.76500 AlM1 0.00000 0.90650 0.25000 0.13800 FeM1 0.00000 0.90650 0.25000 0.04500 TiM1 0.00000 0.90650 0.25000 0.00800 CrM1 0.00000 0.90650 0.25000 0.04400 CaM2 0.00000 0.29570 0.25000 0.64500 NaM2 0.00000 0.29570 0.25000 0.09400 MgM2 0.00000 0.29570 0.25000 0.19200 FeM2 0.00000 0.29570 0.25000 0.06700 MnM2 0.00000 0.29570 0.25000 0.00200 SiT 0.28960 0.09260 0.23530 0.94400 AlT 0.28960 0.09260 0.23530 0.05600 O1 0.11510 0.08650 0.14030 1.00000 O2 0.36470 0.25220 0.32630 1.00000 O3 0.35210 0.01850 0.00100 1.00000