data_Fe3C4
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   7.12
_cell_length_b   7.12
_cell_length_c   7.12
_cell_angle_alpha   156.86
_cell_angle_beta   156.86
_cell_angle_gamma   32.95
_symmetry_Int_Tables_number   1
_chemical_formula_structural   Fe3C4
_chemical_formula_sum   'Fe3 C4'
_cell_volume   55.71
_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
  Fe  Fe4  1  0.0  0.0  0.0  1.0
  Fe  Fe5  1  0.0  0.0  0.25  1.0
  Fe  Fe6  1  0.0  0.0  0.41  1.0
  C  C0  1  0.0  0.0  0.19  1.0
  C  C1  1  0.0  0.0  0.47  1.0
  C  C2  1  0.0  0.0  0.16  1.0
  C  C3  1  0.0  0.0  0.5  1.0

data_Fe3C4
_symmetry_space_group_name_H-M   Cm
_cell_length_a   4.04
_cell_length_b   4.04
_cell_length_c   7.12
_cell_angle_alpha   90.0
_cell_angle_beta   106.47
_cell_angle_gamma   90.0
_symmetry_Int_Tables_number   8
_chemical_formula_structural   Fe3C4
_chemical_formula_sum   'Fe6 C8'
_cell_volume   111.42
_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
  Fe  Fe0  2  0.0  0.0  0.0  1.0
  Fe  Fe1  2  0.0  0.0  0.59  1.0
  Fe  Fe2  2  0.0  0.0  0.75  1.0
  C  C3  2  0.0  0.0  0.5  1.0
  C  C4  2  0.0  0.0  0.53  1.0
  C  C5  2  0.0  0.0  0.81  1.0
  C  C6  2  0.0  0.0  0.84  1.0

Fe Fe Fe C C C C