data_Mg3Ni
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.14
_cell_length_b   5.14
_cell_length_c   5.14
_cell_angle_alpha   132.72
_cell_angle_beta   132.72
_cell_angle_gamma   69.09
_symmetry_Int_Tables_number   1
_chemical_formula_structural   Mg3Ni
_chemical_formula_sum   'Mg3 Ni1'
_cell_volume   71.95
_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
  Mg  Mg1  1  0.06  0.0  0.12  1.0
  Mg  Mg2  1  0.0  0.06  0.12  1.0
  Ni  Ni3  1  0.0  0.0  0.23  1.0

data_Mg3Ni
_symmetry_space_group_name_H-M   Cm
_cell_length_a   5.83
_cell_length_b   5.83
_cell_length_c   5.14
_cell_angle_alpha   90.0
_cell_angle_beta   124.55
_cell_angle_gamma   90.0
_symmetry_Int_Tables_number   8
_chemical_formula_structural   Mg3Ni
_chemical_formula_sum   'Mg6 Ni2'
_cell_volume   143.91
_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  0.41  0.47  0.94  1.0
  Mg  Mg1  2  0.0  0.0  0.0  1.0
  Ni  Ni2  2  0.27  0.5  0.77  1.0

Mg Mg Mg Ni
Mg Mg Mg Ni 0 2 o o o 0 1 o o o 1 2 o o o 1 3 o o o 2 3 o o o 