data_[Na4Mg2Se6]
loop_
 _atom_type_symbol
 _atom_type_electronegativity
 _atom_type_radius
 _atom_type_ionic_radius
[
  Na  0.9300  1.8000  1.1600
  Mg  1.3100  1.5000  0.8600
  Se  2.5500  1.1500  1.0133
]
_symmetry_space_group_name_H-M [P-1]
_cell_length_a [6.0728]
_cell_length_b [6.4133]
_cell_length_c [7.6683]
_cell_angle_alpha [99.0691]
_cell_angle_beta [93.7593]
_cell_angle_gamma [105.5705]
_symmetry_Int_Tables_number [2]
_chemical_formula_structural [Na2MgSe3]
_chemical_formula_sum '[Na4 Mg2 Se6]'
_cell_volume [282.2636]
_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
[
  Na  Na0  2  0.1820  0.8551  0.5258  1.0
  Na  Na1  1  0.0000  0.0000  0.0000  1.0
  Na  Na2  1  0.5000  0.5000  0.5000  1.0
  Mg  Mg3  2  0.3624  0.7076  0.0066  1.0
  Se  Se4  2  0.0470  0.4682  0.2251  1.0
  Se  Se5  2  0.2304  0.3051  0.7649  1.0
  Se  Se6  2  0.4158  0.0772  0.2315  1.0
]