data_[Mg4Si4N8]
loop_
 _atom_type_symbol
 _atom_type_electronegativity
 _atom_type_radius
 _atom_type_ionic_radius
[
  Mg  1.3100  1.5000  0.8600
  Si  1.9000  1.1000  0.5400
  N  3.0400  0.6500  0.6300
]
_symmetry_space_group_name_H-M [Pna2_1]
_cell_length_a [5.3100]
_cell_length_b [6.5036]
_cell_length_c [5.0305]
_cell_angle_alpha [90.0000]
_cell_angle_beta [90.0000]
_cell_angle_gamma [90.0000]
_symmetry_Int_Tables_number [33]
_chemical_formula_structural [MgSiN2]
_chemical_formula_sum '[Mg4 Si4 N8]'
_cell_volume [173.7281]
_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  0.0847  0.6228  0.9886  1.0
  Si  Si1  4  0.0698  0.1254  0.0001  1.0
  N  N2  4  0.0480  0.0951  0.3466  1.0
  N  N3  4  0.1097  0.6558  0.4108  1.0
]