data_[Ca4Cu4As8]
loop_
 _atom_type_symbol
 _atom_type_electronegativity
 _atom_type_radius
 _atom_type_ionic_radius
[
  Ca  1.0000  1.8000  1.1400
  Cu  1.9000  1.3500  0.8200
  As  2.1800  1.1500  0.6600
]
_symmetry_space_group_name_H-M [Cmcm]
_cell_length_a [4.2337]
_cell_length_b [16.4798]
_cell_length_c [4.6219]
_cell_angle_alpha [90.0000]
_cell_angle_beta [90.0000]
_cell_angle_gamma [90.0000]
_symmetry_Int_Tables_number [63]
_chemical_formula_structural [CaCuAs2]
_chemical_formula_sum '[Ca4 Cu4 As8]'
_cell_volume [322.4736]
_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
[
  Ca  Ca0  4  0.0000  0.3963  0.7500  1.0
  Cu  Cu1  4  0.0000  0.1770  0.7500  1.0
  As  As2  4  0.0000  0.0322  0.7500  1.0
  As  As3  4  0.0000  0.2469  0.2500  1.0
]