data_global _chemical_name_mineral 'Ferrosilite' loop_ _publ_author_name 'Smyth J R' _journal_name_full 'American Mineralogist' _journal_volume 58 _journal_year 1973 _journal_page_first 636 _journal_page_last 648 _publ_section_title ; An orthopyroxene structure up to 850 C T = 280 C ; _database_code_amcsd 364 _chemical_formula_sum 'Si2 Mg.636 Fe1.331 Ca.032 O6' _cell_length_a 18.371 _cell_length_b 9.0 _cell_length_c 5.242 _cell_angle_alpha 90.0 _cell_angle_beta 90.0 _cell_angle_gamma 90.0 _cell_volume 866.707 _exptl_crystal_density_diffrn 3.728 _symmetry_space_group_name_H-M 'P b c a' loop_ _space_group_symop_operation_xyz 'x,y,z' 'x,1/2-y,1/2+z' '-x,1/2+y,1/2-z' '1/2-x,1/2+y,z' '1/2+x,1/2-y,-z' '1/2+x,y,1/2-z' '1/2-x,-y,1/2+z' '-x,-y,-z' loop_ _atom_site_label _atom_site_fract_x _atom_site_fract_y _atom_site_fract_z _atom_site_occupancy Sia 0.272 0.3394 0.0542 1.0 Sib 0.4741 0.3358 0.7907 1.0 Mg1 0.3753 0.654 0.8799 0.594 Fe1 0.3753 0.654 0.8799 0.406 Fe2 0.3776 0.4848 0.3738 0.925 Mg2 0.3776 0.4848 0.3738 0.042 Ca2 0.3776 0.4848 0.3738 0.032 O1a 0.1832 0.3376 0.0476 1.0 O2a 0.3116 0.4967 0.0634 1.0 O3a 0.3024 0.2367 -0.1805 1.0 O1b 0.5624 0.3366 0.7867 1.0 O2b 0.4342 0.4845 0.6997 1.0 O3b 0.4477 0.2059 0.5831 1.0 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 Sia 0.00975 0.01387 0.01364 8e-05 0.00078 -0.00048 Sib 0.01265 0.01371 0.01217 0.00067 0.00039 0.00069 Mg1 0.01094 0.01543 0.01132 -0.00067 -0.00185 0.00041 Fe1 0.01094 0.01543 0.01132 -0.00067 -0.00185 0.00041 Fe2 0.01573 0.02048 0.01602 -0.00142 -0.00551 0.00045 Mg2 0.01573 0.02048 0.01602 -0.00142 -0.00551 0.00045 Ca2 0.01573 0.02048 0.01602 -0.00142 -0.00551 0.00045 O1a 0.01231 0.01477 0.01105 -0.00327 -0.00259 -0.00131 O2a 0.01624 0.02003 0.01306 0.00235 0.00161 -0.00674 O3a 0.01214 0.02524 0.02038 -0.00704 -0.0022 0.00574 O1b 0.01522 0.01535 0.01256 -0.00126 -0.00307 -0.00091 O2b 0.01368 0.01609 0.01002 0.00034 0.0059 -0.00535 O3b 0.0094 0.02236 0.01903 -8e-05 -0.00302 -0.00356