data_[Mg4C8]
loop_
 _atom_type_symbol
 _atom_type_electronegativity
 _atom_type_radius
 _atom_type_ionic_radius
[
  Mg  1.3100  1.5000  0.8600
  C  2.5500  0.7000  0.3000
]
_symmetry_space_group_name_H-M [Immm]
_cell_length_a [2.5798]
_cell_length_b [6.2377]
_cell_length_c [6.7865]
_cell_angle_alpha [90.0000]
_cell_angle_beta [90.0000]
_cell_angle_gamma [90.0000]
_symmetry_Int_Tables_number [71]
_chemical_formula_structural [MgC2]
_chemical_formula_sum '[Mg4 C8]'
_cell_volume [109.2074]
_cell_formula_units_Z [4]
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  4  0.0000  0.0000  0.3005  1
  C  C1  4  0.0000  0.2426  0.0000  1
  C  C2  4  0.0000  0.3833  0.5000  1
]