data_Mg2AlSi
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.13
_cell_length_b   5.13
_cell_length_c   5.13
_cell_angle_alpha   132.24
_cell_angle_beta   132.24
_cell_angle_gamma   69.85
_symmetry_Int_Tables_number   1
_chemical_formula_structural   Mg2AlSi
_chemical_formula_sum   'Mg2 Al1 Si1'
_cell_volume   72.57
_cell_formula_units_Z   1
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  Mg1  1  0.08  0.0  0.1  1.0
  Mg  Mg2  1  0.0  0.08  0.1  1.0
  Al  Al0  1  0.0  0.0  0.0  1.0
  Si  Si3  1  0.0  0.0  0.21  1.0

data_Mg2AlSi
_symmetry_space_group_name_H-M   Cm
_cell_length_a   5.87
_cell_length_b   5.87
_cell_length_c   5.13
_cell_angle_alpha   90.0
_cell_angle_beta   124.93
_cell_angle_gamma   90.0
_symmetry_Int_Tables_number   8
_chemical_formula_structural   Mg2AlSi
_chemical_formula_sum   'Mg4 Al2 Si2'
_cell_volume   145.13
_cell_formula_units_Z   2
loop_
 _symmetry_equiv_pos_site_id
 _symmetry_equiv_pos_as_xyz
  1  'x, y, z'
  2  'x, -y, z'
  3  'x+1/2, y+1/2, z'
  4  'x+1/2, -y+1/2, 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  4  0.44  0.46  0.97  1.0
  Al  Al1  2  0.0  0.0  0.0  1.0
  Si  Si2  2  0.29  0.5  0.79  1.0

Mg Mg Al Si