data_[Si2C4N8]
loop_
 _atom_type_symbol
 _atom_type_electronegativity
 _atom_type_radius
 _atom_type_ionic_radius
[
  Si  1.9000  1.1000  0.5400
  C  2.5500  0.7000  0.3000
  N  3.0400  0.6500  0.6300
]
_symmetry_space_group_name_H-M [Pn-3m]
_cell_length_a [6.6844]
_cell_length_b [6.6844]
_cell_length_c [6.6844]
_cell_angle_alpha [90.0000]
_cell_angle_beta [90.0000]
_cell_angle_gamma [90.0000]
_symmetry_Int_Tables_number [224]
_chemical_formula_structural [Si(CN2)2]
_chemical_formula_sum '[Si2 C4 N8]'
_cell_volume [298.6641]
_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
[
  Si  Si0  2  0.0000  0.0000  0.0000  1.0
  C  C1  4  0.2500  0.2500  0.7500  1.0
  N  N2  8  0.1455  0.1455  0.8545  1.0
]