data_[Sm6Si2N8]
loop_
 _atom_type_symbol
 _atom_type_electronegativity
 _atom_type_radius
 _atom_type_ionic_radius
[
  Sm  1.1700  1.8500  1.2290
  Si  1.9000  1.1000  0.5400
  N  3.0400  0.6500  0.6300
]
_symmetry_space_group_name_H-M [Pmn2_1]
_cell_length_a [7.4543]
_cell_length_b [6.5808]
_cell_length_c [5.3757]
_cell_angle_alpha [90.0000]
_cell_angle_beta [90.0000]
_cell_angle_gamma [90.0000]
_symmetry_Int_Tables_number [31]
_chemical_formula_structural [Sm3SiN4]
_chemical_formula_sum '[Sm6 Si2 N8]'
_cell_volume [263.7115]
_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
[
  Sm  Sm0  4  0.2498  0.6653  0.0307  1
  Sm  Sm1  2  0.0000  0.8491  0.5305  1
  Si  Si2  2  0.0000  0.1682  0.9989  1
  N  N3  4  0.2016  0.2984  0.0875  1
  N  N4  2  0.0000  0.1703  0.6694  1
  N  N5  2  0.0000  0.8997  0.0800  1
]