data_[Rb2Mg2Ni2Se6]
loop_
 _atom_type_symbol
 _atom_type_electronegativity
 _atom_type_radius
 _atom_type_ionic_radius
[
  Rb  0.8200  2.3500  1.6600
  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 [P2_1/m]
_cell_length_a [8.1459]
_cell_length_b [3.7557]
_cell_length_c [10.8292]
_cell_angle_alpha [90.0000]
_cell_angle_beta [109.4675]
_cell_angle_gamma [90.0000]
_symmetry_Int_Tables_number [11]
_chemical_formula_structural [RbMgNiSe3]
_chemical_formula_sum '[Rb2 Mg2 Ni2 Se6]'
_cell_volume [312.3680]
_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
[
  Rb  Rb0  2  0.4990  0.7500  0.7834  1
  Mg  Mg1  2  0.0085  0.7500  0.1272  1
  Ni  Ni2  2  0.0615  0.2500  0.3914  1
  Se  Se3  2  0.1280  0.2500  0.6275  1
  Se  Se4  2  0.2070  0.7500  0.9762  1
  Se  Se5  2  0.2378  0.7500  0.3691  1
]