data_global _amcsd_formula_title 'Mg2SiO4' loop_ _publ_author_name 'Baur W H' _journal_name_full 'American Mineralogist' _journal_volume 57 _journal_year 1972 _journal_page_first 709 _journal_page_last 731 _publ_section_title ; Computer-simulated crystal structures of observed and hypothetical Mg2SiO4 polymorphs of low and high density Model I ; _database_code_amcsd 0000280 _chemical_compound_source 'hypothetical' _chemical_formula_sum 'Si Mg2 O4' _cell_length_a 10.11 _cell_length_b 5.77 _cell_length_c 4.70 _cell_angle_alpha 90 _cell_angle_beta 90. _cell_angle_gamma 90 _cell_volume 274.173 _exptl_crystal_density_diffrn 3.408 _symmetry_space_group_name_H-M 'P 1 2/m 1' loop_ _space_group_symop_operation_xyz 'x,y,z' 'x,-y,z' '-x,y,-z' '-x,-y,-z' loop_ _atom_site_label _atom_site_fract_x _atom_site_fract_y _atom_site_fract_z Si1 0.84200 0.50000 0.87520 Si2 0.32260 0.00000 0.88240 Mg1 0.50000 0.50000 0.00000 Mg2 0.00000 0.00000 0.50000 Mg3 0.00000 0.50000 0.50000 Mg4 0.50000 0.00000 0.50000 Mg5 0.24820 0.25270 0.49900 O1 0.31540 0.50000 0.21050 O2 0.16420 0.50000 0.77570 O3 0.83050 0.00000 0.23340 O4 0.33300 0.00000 0.23090 O5 0.08510 0.26010 0.22870 O6 0.59320 0.22810 0.22100