data_[Mg2Cu2As2]
loop_
 _atom_type_symbol
 _atom_type_electronegativity
 _atom_type_radius
 _atom_type_ionic_radius
[
  Mg  1.3100  1.5000  0.8600
  Cu  1.9000  1.3500  0.8200
  As  2.1800  1.1500  0.6600
]
_symmetry_space_group_name_H-M [P3m1]
_cell_length_a [4.1839]
_cell_length_b [4.1839]
_cell_length_c [7.4893]
_cell_angle_alpha [90.0000]
_cell_angle_beta [90.0000]
_cell_angle_gamma [120.0000]
_symmetry_Int_Tables_number [156]
_chemical_formula_structural [MgCuAs]
_chemical_formula_sum '[Mg2 Cu2 As2]'
_cell_volume [113.5379]
_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
[
  Mg  Mg0  1  0.0000  0.0000  0.5176  1.0
  Mg  Mg1  1  0.3333  0.6667  0.8360  1.0
  Cu  Cu2  1  0.0000  0.0000  0.1678  1.0
  Cu  Cu3  1  0.6667  0.3333  0.3254  1.0
  As  As4  1  0.3333  0.6667  0.1873  1.0
  As  As5  1  0.6667  0.3333  0.6708  1.0
]