data_global _chemical_name_mineral 'Forsterite' loop_ _publ_author_name 'Hazen R M' _journal_name_full 'American Mineralogist' _journal_volume 61 _journal_year 1976 _journal_page_first 1280 _journal_page_last 1293 _publ_section_title ; Effects of temperature and pressure on the crystal structure of forsterite T = 1000 C P = 1 atm olivine ; _database_code_amcsd 0000549 _chemical_formula_sum 'Si Mg2 O4' _cell_length_a 4.795 _cell_length_b 10.36 _cell_length_c 6.06 _cell_angle_alpha 90 _cell_angle_beta 90 _cell_angle_gamma 90 _cell_volume 301.038 _exptl_crystal_density_diffrn 3.104 _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 Si 0.42630 0.09430 0.25000 Mg1 0.00000 0.00000 0.00000 Mg2 0.99240 0.27720 0.25000 O1 0.76310 0.09140 0.25000 O2 0.21780 0.44970 0.25000 O3 0.28430 0.16290 0.03590 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 Si 0.00792 0.01468 0.01433 0.00101 0.00000 0.00000 Mg1 0.01794 0.03208 0.01712 -0.00101 -0.00250 -0.00541 Mg2 0.02132 0.02066 0.02270 0.00126 0.00000 0.00000 O1 0.01374 0.02338 0.02009 0.01158 0.00000 0.00000 O2 0.01572 0.01740 0.01972 0.00000 0.00000 0.00000 O3 0.01899 0.02447 0.01916 -0.00075 -0.00074 0.00604