data_[Na2Mg2Fe2Se4O16]
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
  Fe  1.8300  1.4000  0.8525
  Se  2.5500  1.1500  1.0133
  O  3.4400  0.6000  1.2600
]
_symmetry_space_group_name_H-M [C2]
_cell_length_a [8.3181]
_cell_length_b [6.2680]
_cell_length_c [7.3160]
_cell_angle_alpha [90.0000]
_cell_angle_beta [90.1915]
_cell_angle_gamma [90.0000]
_symmetry_Int_Tables_number [5]
_chemical_formula_structural [NaMgFe(SeO4)2]
_chemical_formula_sum '[Na2 Mg2 Fe2 Se4 O16]'
_cell_volume [381.4348]
_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  0.0000  0.1753  0.5000  1
  Mg  Mg1  2  0.0000  0.6881  0.5000  1
  Fe  Fe2  2  0.0000  0.9826  0.0000  1
  Se  Se3  4  0.1198  0.4796  0.8022  1
  O  O4  4  0.0128  0.7372  0.7743  1
  O  O5  4  0.0228  0.2350  0.8008  1
  O  O6  4  0.1903  0.4854  0.5769  1
  O  O7  4  0.2427  0.9899  0.0304  1
]