data_Mg3C2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   6.2
_cell_length_b   6.2
_cell_length_c   6.2
_cell_angle_alpha   52.95
_cell_angle_beta   52.95
_cell_angle_gamma   52.95
_symmetry_Int_Tables_number   1
_chemical_formula_structural   Mg3C2
_chemical_formula_sum   'Mg6 C4'
_cell_volume   140.41
_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  Mg4  1  0.84  0.26  0.3  1.0
  Mg  Mg5  1  0.07  0.15  0.3  1.0
  Mg  Mg6  1  0.09  0.59  0.3  1.0
  Mg  Mg7  1  0.91  0.41  0.64  1.0
  Mg  Mg8  1  0.93  0.85  0.64  1.0
  Mg  Mg9  1  0.16  0.74  0.64  1.0
  C  C0  1  0.0  0.0  0.53  1.0
  C  C1  1  0.0  0.0  0.37  1.0
  C  C2  1  0.0  0.0  0.56  1.0
  C  C3  1  0.0  0.0  0.4  1.0

data_Mg3C2
_symmetry_space_group_name_H-M   P-1
_cell_length_a   5.52
_cell_length_b   5.52
_cell_length_c   6.2
_cell_angle_alpha   63.53
_cell_angle_beta   63.53
_cell_angle_gamma   60.0
_symmetry_Int_Tables_number   2
_chemical_formula_structural   Mg3C2
_chemical_formula_sum   'Mg6 C4'
_cell_volume   140.41
_cell_formula_units_Z   2
loop_
 _symmetry_equiv_pos_site_id
 _symmetry_equiv_pos_as_xyz
  1  'x, y, z'
  2  '-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  2  0.15  0.33  0.95  1.0
  Mg  Mg1  2  0.26  0.33  0.08  1.0
  Mg  Mg2  2  0.41  0.67  0.51  1.0
  C  C3  2  0.0  0.4  0.1  1.0
  C  C4  2  0.0  0.44  0.06  1.0

Mg Mg Mg Mg Mg Mg C C C C