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 = 20 C ; _database_code_amcsd 362 _chemical_formula_sum 'Si2 Mg.636 Fe1.331 Ca.032 O6' _cell_length_a 18.337 _cell_length_b 8.971 _cell_length_c 5.232 _cell_angle_alpha 90.0 _cell_angle_beta 90.0 _cell_angle_gamma 90.0 _cell_volume 860.67 _exptl_crystal_density_diffrn 3.754 _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 0.27182 0.33967 0.05188 1.0 Sib 0.47391 0.3356 0.79182 1.0 Mg1 0.37546 0.65459 0.87652 0.574 Fe1 0.37546 0.65459 0.87652 0.425 Fe2 0.37779 0.48398 0.39643 0.906 Mg2 0.37779 0.48398 0.39643 0.062 Ca2 0.37779 0.48398 0.39643 0.032 O1a 0.1838 0.3376 0.0441 1.0 O2a 0.3113 0.4991 0.057 1.0 O3a 0.3023 0.2347 -0.179 1.0 O1b 0.5623 0.3361 0.791 1.0 O2b 0.434 0.4842 0.6965 1.0 O3b 0.4475 0.2034 0.588 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 0.00562 0.00624 0.00721 -0.00058 0.00136 -0.0009 Sib 0.00494 0.00681 0.00624 0.00042 -0.0001 0.00059 Mg1 0.00698 0.00669 0.00661 0.0 -0.00053 5e-05 Fe1 0.00698 0.00669 0.00661 0.0 -0.00053 5e-05 Fe2 0.00698 0.00909 0.00734 -0.00083 -0.00253 0.00026 Mg2 0.00698 0.00909 0.00734 -0.00083 -0.00253 0.00026 Ca2 0.00698 0.00909 0.00734 -0.00083 -0.00253 0.00026 O1a 0.00409 0.00677 0.00899 -8e-05 -0.00049 -0.00026 O2a 0.01056 0.00673 0.01058 -0.00183 -0.00097 0.00071 O3a 0.00562 0.01272 0.00793 -0.00242 0.00058 -0.00521 O1b 0.00426 0.0097 0.00659 -8e-05 -0.00102 0.00088 O2b 0.0063 0.00974 0.00972 8e-05 0.00185 0.0014 O3b 0.00511 0.01378 0.0051 0.00258 -0.00117 -0.00247