data_MgSi2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   3.91
_cell_length_b   4.96
_cell_length_c   5.73
_cell_angle_alpha   76.49
_cell_angle_beta   88.94
_cell_angle_gamma   67.22
_symmetry_Int_Tables_number   1
_chemical_formula_structural   MgSi2
_chemical_formula_sum   'Mg2 Si4'
_cell_volume   99.42
_cell_formula_units_Z   2
loop_
 _symmetry_equiv_pos_site_id
 _symmetry_equiv_pos_as_xyz
  1  'x, y, z'
loop_
 _atom_site_type_symbol
 _atom_site_label
 _atom_site_symmetry_multiplicity
 _atom_site_fract_x
 _atom_site_fract_y
 _atom_site_fract_z
 _atom_site_occupancy
  Mg  Mg0  1  0.98  0.22  0.58  1.0
  Mg  Mg1  1  0.96  0.76  0.98  1.0
  Si  Si2  1  0.0  0.0  0.0  1.0
  Si  Si3  1  0.05  0.7  0.78  1.0
  Si  Si4  1  0.91  0.62  0.86  1.0
  Si  Si5  1  0.02  0.36  0.7  1.0

data_MgSi2
_symmetry_space_group_name_H-M   P1
_cell_length_a   3.91
_cell_length_b   4.96
_cell_length_c   5.73
_cell_angle_alpha   76.49
_cell_angle_beta   88.94
_cell_angle_gamma   67.22
_symmetry_Int_Tables_number   1
_chemical_formula_structural   MgSi2
_chemical_formula_sum   'Mg2 Si4'
_cell_volume   99.42
_cell_formula_units_Z   2
loop_
 _symmetry_equiv_pos_site_id
 _symmetry_equiv_pos_as_xyz
  1  'x, y, z'
loop_
 _atom_site_type_symbol
 _atom_site_label
 _atom_site_symmetry_multiplicity
 _atom_site_fract_x
 _atom_site_fract_y
 _atom_site_fract_z
 _atom_site_occupancy
  Mg  Mg0  1  0.96  0.76  0.98  1.0
  Mg  Mg1  1  0.98  0.22  0.58  1.0
  Si  Si2  1  0.0  0.0  0.0  1.0
  Si  Si3  1  0.02  0.36  0.7  1.0
  Si  Si4  1  0.05  0.7  0.78  1.0
  Si  Si5  1  0.91  0.62  0.86  1.0

Mg Mg Si Si Si Si