data_global
_chemical_name_mineral 'Forsterite'
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
;
_database_code_amcsd 0000276
_chemical_compound_source 'hypothetical'
_chemical_formula_sum 'Si Mg2 O4'
_cell_length_a 4.79
_cell_length_b 10.19
_cell_length_c 5.85
_cell_angle_alpha 90
_cell_angle_beta 90
_cell_angle_gamma 90
_cell_volume 285.539
_exptl_crystal_density_diffrn      3.273
_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   0.09450   0.40780   0.25000
Mg1   0.00000   0.00000   0.00000
Mg2   0.00560   0.26320   0.75000
O1   0.24990   0.09070   0.75000
O2   0.28320   0.05780   0.25000
O3   0.23120   0.33700   0.47070