data_NaC
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   4.34
_cell_length_b   4.34
_cell_length_c   4.34
_cell_angle_alpha   37.55
_cell_angle_beta   37.55
_cell_angle_gamma   37.55
_symmetry_Int_Tables_number   1
_chemical_formula_structural   NaC
_chemical_formula_sum   'Na1 C1'
_cell_volume   27.22
_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
  Na  Na1  1  0.0  0.0  0.04  1.0
  C  C0  1  0.0  0.0  0.0  1.0

data_NaC
_symmetry_space_group_name_H-M   Cm
_cell_length_a   4.84
_cell_length_b   2.79
_cell_length_c   4.34
_cell_angle_alpha   90.0
_cell_angle_beta   111.82
_cell_angle_gamma   90.0
_symmetry_Int_Tables_number   8
_chemical_formula_structural   NaC
_chemical_formula_sum   'Na2 C2'
_cell_volume   54.43
_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
  Na  Na0  2  0.0  0.0  0.96  1.0
  C  C1  2  0.0  0.0  0.0  1.0

Na C
Na C 0 1 o o o 