data_global _chemical_name_mineral 'Forsterite' loop_ _publ_author_name 'Merli M' 'Oberti R' 'Caucia F' 'Ungaretti L' _journal_name_full 'American Mineralogist' _journal_volume 86 _journal_year 2001 _journal_page_first 55 _journal_page_last 65 _publ_section_title ; Determination of site population in olivine: Warnings on X-ray data treatment and refinement Sample: F-refinement using CRYSTALS on the 2491 reflections with Fo/sFo>1 Fo92Fa08 ; _database_code_amcsd 0002603 _chemical_formula_sum '(Mg1.85 Fe.15) Si O4' _cell_length_a 4.7579 _cell_length_b 10.2151 _cell_length_c 5.9890 _cell_angle_alpha 90 _cell_angle_beta 90 _cell_angle_gamma 90 _cell_volume 291.080 _exptl_crystal_density_diffrn 3.318 _symmetry_space_group_name_H-M 'P b n m' loop_ _space_group_symop_operation_xyz 'x,y,z' 'x,y,1/2-z' '-x,-y,1/2+z' '1/2+x,1/2-y,1/2+z' '1/2-x,1/2+y,1/2-z' '1/2-x,1/2+y,z' '1/2+x,1/2-y,-z' '-x,-y,-z' loop_ _atom_site_label _atom_site_fract_x _atom_site_fract_y _atom_site_fract_z _atom_site_occupancy Mg1 0.00000 0.00000 0.00000 0.92000 Fe1 0.00000 0.00000 0.00000 0.08000 Mg2 0.99010 0.27760 0.25000 0.93000 Fe2 0.99010 0.27760 0.25000 0.07000 Si 0.42670 0.09430 0.25000 1.00000 O1 0.76600 0.09170 0.25000 1.00000 O2 0.22080 0.44750 0.25000 1.00000 O3 0.27810 0.16330 0.03330 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 Mg1 0.00474 0.00639 0.00509 -0.00014 -0.00061 -0.00110 Fe1 0.00474 0.00639 0.00509 -0.00014 -0.00061 -0.00110 Mg2 0.00618 0.00432 0.00596 0.00017 0.00000 0.00000 Fe2 0.00618 0.00432 0.00596 0.00017 0.00000 0.00000 Si 0.00309 0.00374 0.00447 0.00011 0.00000 0.00000 O1 0.00361 0.00651 0.00605 0.00013 0.00000 0.00000 O2 0.00551 0.00385 0.00647 -0.00008 0.00000 0.00000 O3 0.00545 0.00620 0.00573 0.00027 -0.00015 0.00156