data_global _chemical_name_mineral 'Hedenbergite' loop_ _publ_author_name 'Abdu Y A' 'Hawthorne F C' _journal_name_full 'American Mineralogist' _journal_volume 98 _journal_year 2013 _journal_page_first 1227 _journal_page_last 1234 _publ_section_title ; Local structure in C2/c clinopyroxenes on the hedenbergite (CaFeSi2O6)- ferrosilite (Fe2Si2O6) join: A new interpretation for the Mossbauer spectra of Ca-rich C2/c clinopyroxenes and implications for pyroxene exsolution Note split-M2-O2-O3 model Sample: Hd70Fs30 ; _database_code_amcsd 0019863 _chemical_compound_source 'Synthetic' _chemical_formula_sum 'Fe1.3 Ca.7 Si2 O6' _cell_length_a 9.819 _cell_length_b 9.056 _cell_length_c 5.242 _cell_angle_alpha 90 _cell_angle_beta 105.61 _cell_angle_gamma 90 _cell_volume 448.931 _exptl_crystal_density_diffrn 3.741 _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 FeM1 0.00000 0.90619 0.25000 1.00000 0.00886 FeM2 0.00000 0.29980 0.25000 0.30000 0.01030 CaM2* 0.00000 0.26270 0.25000 0.70000 0.01030 SiT 0.29077 0.09098 0.23797 1.00000 0.00819 O1 0.12074 0.08997 0.15300 1.00000 0.00960 O2* 0.36140 0.24680 0.32020 0.70000 0.00990 O2** 0.38080 0.23700 0.37450 0.30000 0.00990 O3* 0.36200 0.01900 0.01100 0.70000 0.01030 O3** 0.34630 0.02460 -0.01100 0.30000 0.01030