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 = 175 C note temperature factors for O1b appear incorrect ; _database_code_amcsd 363 _chemical_formula_sum 'Mg.635 Fe1.332 Ca.032 Si2 O6' _cell_length_a 18.364 _cell_length_b 8.988 _cell_length_c 5.238 _cell_angle_alpha 90.0 _cell_angle_beta 90.0 _cell_angle_gamma 90.0 _cell_volume 864.561 _exptl_crystal_density_diffrn 3.738 _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 Mg1 0.3754 0.6543 0.8783 0.596 Fe1 0.3754 0.6543 0.8783 0.403 Fe2 0.3777 0.4844 0.3715 0.929 Mg2 0.3777 0.4844 0.3715 0.039 Ca2 0.3777 0.4844 0.3715 0.032 Sia 0.2719 0.3399 0.0531 1.0 Sib 0.474 0.3356 0.7917 1.0 O1a 0.1834 0.3374 0.0454 1.0 O2a 0.3114 0.498 0.0616 1.0 O3a 0.3025 0.2353 -0.1807 1.0 O1b 0.5623 0.3363 0.7879 1.0 O2b 0.4341 0.4847 0.6994 1.0 O3b 0.4477 0.2043 0.5858 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 Mg1 0.00996 0.01105 0.00933 -0.0007 -0.00066 -0.00018 Fe1 0.00996 0.01105 0.00933 -0.0007 -0.00066 -0.00018 Fe2 0.01336 0.01601 0.0125 -0.00054 -0.00384 0.0001 Mg2 0.01336 0.01601 0.0125 -0.00054 -0.00384 0.0001 Ca2 0.01336 0.01601 0.0125 -0.00054 -0.00384 0.0001 Sia 0.00981 0.01 0.01232 0.0 0.0 0.0 Sib 0.01143 0.01106 0.00979 -0.00011 7e-05 0.00014 O1a 0.01237 0.01184 0.00815 -0.00058 -0.00054 -0.00162 O2a 0.01327 0.01667 0.00895 -0.00171 -0.00061 -0.00432 O3a 0.01203 0.02348 0.01647 -0.00675 0.00054 0.00439 O1b 0.00593 0.01359 0.00897 -0.00188 -0.00027 -0.0009 O2b 0.01063 0.01717 0.00965 0.00035 0.00429 -0.00217 O3b 0.00801 0.01826 0.01733 -0.00232 -0.00098 -0.00522