data_MgSi2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   4.54
_cell_length_b   5.12
_cell_length_c   10.19
_cell_angle_alpha   79.55
_cell_angle_beta   78.08
_cell_angle_gamma   64.48
_symmetry_Int_Tables_number   1
_chemical_formula_structural   MgSi2
_chemical_formula_sum   'Mg4 Si8'
_cell_volume   208.15
_cell_formula_units_Z   4
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  0.4  0.18  0.57  1.0
  Mg  Mg1  1  0.43  0.83  0.96  1.0
  Mg  Mg2  1  0.46  0.49  0.35  1.0
  Mg  Mg3  1  0.0  0.0  0.0  1.0
  Si  Si4  1  0.19  0.05  0.24  1.0
  Si  Si5  1  0.36  0.0  0.51  1.0
  Si  Si6  1  0.51  0.77  0.2  1.0
  Si  Si7  1  0.49  0.66  0.41  1.0
  Si  Si8  1  0.64  0.15  0.72  1.0
  Si  Si9  1  0.66  0.61  0.68  1.0
  Si  Si10  1  0.21  0.52  0.2  1.0
  Si  Si11  1  0.34  0.9  0.72  1.0

data_MgSi2
_symmetry_space_group_name_H-M   P1
_cell_length_a   4.54
_cell_length_b   5.12
_cell_length_c   10.19
_cell_angle_alpha   79.55
_cell_angle_beta   78.08
_cell_angle_gamma   64.48
_symmetry_Int_Tables_number   1
_chemical_formula_structural   MgSi2
_chemical_formula_sum   'Mg4 Si8'
_cell_volume   208.15
_cell_formula_units_Z   4
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  0.0  0.0  0.0  1.0
  Mg  Mg1  1  0.4  0.18  0.57  1.0
  Mg  Mg2  1  0.43  0.83  0.96  1.0
  Mg  Mg3  1  0.46  0.49  0.35  1.0
  Si  Si4  1  0.19  0.05  0.24  1.0
  Si  Si5  1  0.21  0.52  0.2  1.0
  Si  Si6  1  0.34  0.9  0.72  1.0
  Si  Si7  1  0.36  0.0  0.51  1.0
  Si  Si8  1  0.49  0.66  0.41  1.0
  Si  Si9  1  0.51  0.77  0.2  1.0
  Si  Si10  1  0.64  0.15  0.72  1.0
  Si  Si11  1  0.66  0.61  0.68  1.0

Mg Mg Mg Mg Si Si Si Si Si Si Si Si