data_[Er28Ru4Se20]
loop_
 _atom_type_symbol
 _atom_type_electronegativity
 _atom_type_radius
 _atom_type_ionic_radius
[
  Er  1.2400  1.7500  1.0300
  Ru  2.2000  1.3000  0.6610
  Se  2.5500  1.1500  1.0133
]
_symmetry_space_group_name_H-M [Cmc2_1]
_cell_length_a [3.9057]
_cell_length_b [13.3121]
_cell_length_c [24.3646]
_cell_angle_alpha [90.0000]
_cell_angle_beta [90.0000]
_cell_angle_gamma [90.0000]
_symmetry_Int_Tables_number [36]
_chemical_formula_structural [Er7RuSe5]
_chemical_formula_sum '[Er28 Ru4 Se20]'
_cell_volume [1266.8067]
_cell_formula_units_Z [4]
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
[
  Er  Er0  4  0.0000  0.0443  0.7482  1
  Er  Er1  4  0.0000  0.1328  0.4657  1
  Er  Er2  4  0.0000  0.1458  0.0390  1
  Er  Er3  4  0.0000  0.2861  0.6825  1
  Er  Er4  4  0.0000  0.3059  0.8167  1
  Er  Er5  4  0.0000  0.3925  0.3691  1
  Er  Er6  4  0.0000  0.4196  0.1141  1
  Ru  Ru7  4  0.0000  0.3096  0.2589  1
  Se  Se8  4  0.0000  0.0478  0.3600  1
  Se  Se9  4  0.0000  0.0641  0.1443  1
  Se  Se10  4  0.0000  0.2145  0.5722  1
  Se  Se11  4  0.0000  0.2273  0.9289  1
  Se  Se12  4  0.0000  0.4919  0.5003  1
]