data_global _chemical_name_mineral 'Hedenbergite' loop_ _publ_author_name 'Cameron M' 'Sueno S' 'Prewitt C T' 'Papike J J' _journal_name_full 'American Mineralogist' _journal_volume 58 _journal_year 1973 _journal_page_first 594 _journal_page_last 618 _publ_section_title ; High-temperature crystal chemistry of acmite, diopside, hedenbergite, jadeite, spodumene, and ureyite T = 900 C pyroxene ; _database_code_amcsd 0000349 _chemical_formula_sum 'Si2 Fe Ca O6' _cell_length_a 9.906 _cell_length_b 9.164 _cell_length_c 5.273 _cell_angle_alpha 90 _cell_angle_beta 105.22 _cell_angle_gamma 90 _cell_volume 461.886 _exptl_crystal_density_diffrn 3.568 _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 Si 0.28720 0.09150 0.23270 Fe1 0.00000 0.90510 0.25000 Ca2 0.00000 0.29870 0.25000 O1 0.11930 0.08890 0.15060 O2 0.36170 0.24290 0.31880 O3 0.34860 0.01620 0.99730 loop_ _atom_site_aniso_label _atom_site_aniso_U_11 _atom_site_aniso_U_22 _atom_site_aniso_U_33 _atom_site_aniso_U_12 _atom_site_aniso_U_13 _atom_site_aniso_U_23 Si 0.01625 0.01817 0.01464 -0.00120 0.00392 -0.00076 Fe1 0.02291 0.02310 0.01865 0.00000 0.00301 0.00000 Ca2 0.04226 0.02497 0.02593 0.00000 -0.00217 0.00000 O1 0.01726 0.03059 0.02433 -0.00089 0.00488 -0.00002 O2 0.03809 0.02404 0.03091 -0.00861 0.00611 -0.00149 O3 0.02393 0.03225 0.02227 0.00022 0.00796 -0.01082