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 III
;
_database_code_amcsd 0000282
_chemical_compound_source 'hypothetical'
_chemical_formula_sum 'Si Mg2 O4'
_cell_length_a 10.03
_cell_length_b 5.77
_cell_length_c 4.52
_cell_angle_alpha 90
_cell_angle_beta 90.0
_cell_angle_gamma 90
_cell_volume 261.586
_exptl_crystal_density_diffrn      3.572
_symmetry_space_group_name_H-M 'C 1 2/m 1'
loop_
_space_group_symop_operation_xyz
  'x,y,z'
  '1/2+x,1/2+y,z'
  'x,-y,z'
  '1/2+x,1/2-y,z'
  '-x,y,-z'
  '1/2-x,1/2+y,-z'
  '-x,-y,-z'
  '1/2-x,1/2-y,-z'
loop_
_atom_site_label
_atom_site_fract_x
_atom_site_fract_y
_atom_site_fract_z
Si   0.33090   0.00000   0.85380
Mg1   0.00000   0.00000   0.50000
Mg2   0.50000   0.00000   0.50000
Mg3   0.25000   0.25000   0.50000
O1   0.82920   0.00000   0.22190
O2   0.33370   0.00000   0.21630
O3   0.08640   0.26060   0.21960