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 0000362 _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 _cell_angle_beta 90 _cell_angle_gamma 90 _cell_volume 860.670 _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 1.00000 Sib 0.47391 0.33560 0.79182 1.00000 Mg1 0.37546 0.65459 0.87652 0.57400 Fe1 0.37546 0.65459 0.87652 0.42500 Fe2 0.37779 0.48398 0.39643 0.90600 Mg2 0.37779 0.48398 0.39643 0.06200 Ca2 0.37779 0.48398 0.39643 0.03200 O1a 0.18380 0.33760 0.04410 1.00000 O2a 0.31130 0.49910 0.05700 1.00000 O3a 0.30230 0.23470 -0.17900 1.00000 O1b 0.56230 0.33610 0.79100 1.00000 O2b 0.43400 0.48420 0.69650 1.00000 O3b 0.44750 0.20340 0.58800 1.00000 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 -0.00090 Sib 0.00494 0.00681 0.00624 0.00042 -0.00010 0.00059 Mg1 0.00698 0.00669 0.00661 0.00000 -0.00053 0.00005 Fe1 0.00698 0.00669 0.00661 0.00000 -0.00053 0.00005 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 -0.00008 -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 0.00970 0.00659 -0.00008 -0.00102 0.00088 O2b 0.00630 0.00974 0.00972 0.00008 0.00185 0.00140 O3b 0.00511 0.01378 0.00510 0.00258 -0.00117 -0.00247