data_[Mg6Ni6Se6]
loop_
 _atom_type_symbol
 _atom_type_electronegativity
 _atom_type_radius
 _atom_type_ionic_radius
[
  Mg  1.3100  1.5000  0.8600
  Ni  1.9100  1.3500  0.7400
  Se  2.5500  1.1500  1.0133
]
_symmetry_space_group_name_H-M [R3m]
_cell_length_a [4.0429]
_cell_length_b [4.0429]
_cell_length_c [22.7722]
_cell_angle_alpha [90.0000]
_cell_angle_beta [90.0000]
_cell_angle_gamma [120.0000]
_symmetry_Int_Tables_number [160]
_chemical_formula_structural [MgNiSe]
_chemical_formula_sum '[Mg6 Ni6 Se6]'
_cell_volume [322.3395]
_cell_formula_units_Z [6]
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  3  0.0000  0.0000  0.5080  1
  Mg  Mg1  3  0.0000  0.0000  0.7048  1
  Ni  Ni2  3  0.0000  0.0000  0.0016  1
  Ni  Ni3  3  0.0000  0.0000  0.2943  1
  Se  Se4  3  0.0000  0.0000  0.1057  1
  Se  Se5  3  0.0000  0.0000  0.9033  1
]