data_MgP4
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.2
_cell_length_b   5.2
_cell_length_c   5.2
_cell_angle_alpha   126.3
_cell_angle_beta   126.3
_cell_angle_gamma   79.4
_symmetry_Int_Tables_number   1
_chemical_formula_structural   MgP4
_chemical_formula_sum   'Mg1 P4'
_cell_volume   88.14
_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  Mg0  1  0.0  0.0  0.0  1.0
  P  P1  1  0.35  0.0  1.0  1.0
  P  P2  1  0.0  0.35  1.0  1.0
  P  P3  1  0.0  0.0  0.43  1.0
  P  P4  1  0.0  0.0  0.57  1.0

data_MgP4
_symmetry_space_group_name_H-M   Cm
_cell_length_a   6.64
_cell_length_b   6.64
_cell_length_c   5.2
_cell_angle_alpha   90.0
_cell_angle_beta   129.7
_cell_angle_gamma   90.0
_symmetry_Int_Tables_number   8
_chemical_formula_structural   MgP4
_chemical_formula_sum   'Mg2 P8'
_cell_volume   176.28
_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  2  0.0  0.0  0.0  1.0
  P  P1  4  0.17  0.17  0.35  1.0
  P  P2  2  0.07  0.5  0.57  1.0
  P  P3  2  0.43  0.0  0.43  1.0

Mg P P P P