data_global _chemical_name_mineral 'Kosmochlor' loop_ _publ_author_name 'Origlieri M J' 'Downs R T' 'Thompson R M' 'Pommier C J S' 'Denton M B' 'Harlow G E' _journal_name_full 'American Mineralogist' _journal_volume 88 _journal_year 2003 _journal_page_first 1025 _journal_page_last 1032 _publ_section_title ; High-pressure crystal structure of kosmochlor, NaCrSi2O6, and systematics of anisotropic compression in pyroxenes Sample: P = 7.08 GPa ; _database_code_amcsd 0003140 _chemical_formula_sum 'Na Cr Si2 O6' _cell_length_a 9.4110 _cell_length_b 8.5517 _cell_length_c 5.1729 _cell_angle_alpha 90 _cell_angle_beta 106.910 _cell_angle_gamma 90 _cell_volume 398.315 _exptl_crystal_density_diffrn 3.788 _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 Na2 0.00000 0.30580 0.25000 0.01646 Cr1 0.00000 0.90880 0.25000 0.01064 Si 0.29270 0.09360 0.23550 0.01203 O1 0.11600 0.08130 0.14000 0.01013 O2 0.36200 0.26270 0.31300 0.01520 O3 0.35800 0.01720 0.00200 0.01355