data_[Er2Ni2As2O2]
loop_
 _atom_type_symbol
 _atom_type_electronegativity
 _atom_type_radius
 _atom_type_ionic_radius
[
  Er  1.2400  1.7500  1.0300
  Ni  1.9100  1.3500  0.7400
  As  2.1800  1.1500  0.6600
  O  3.4400  0.6000  1.2600
]
_symmetry_space_group_name_H-M [Pmc2_1]
_cell_length_a [4.3698]
_cell_length_b [5.8798]
_cell_length_c [5.7529]
_cell_angle_alpha [90.0000]
_cell_angle_beta [90.0000]
_cell_angle_gamma [90.0000]
_symmetry_Int_Tables_number [26]
_chemical_formula_structural [ErNiAsO]
_chemical_formula_sum '[Er2 Ni2 As2 O2]'
_cell_volume [147.8119]
_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
[
  Er  Er0  2  0.0000  0.2539  0.4159  1
  Ni  Ni1  2  0.5000  0.3657  0.0358  1
  As  As2  2  0.0000  0.2349  0.9176  1
  O  O3  2  0.5000  0.3288  0.3847  1
]