data_[K4Mg2Cu2]
loop_
 _atom_type_symbol
 _atom_type_electronegativity
 _atom_type_radius
 _atom_type_ionic_radius
[
  K  0.8200  2.2000  1.5200
  Mg  1.3100  1.5000  0.8600
  Cu  1.9000  1.3500  0.8200
]
_symmetry_space_group_name_H-M [Imm2]
_cell_length_a [3.9139]
_cell_length_b [6.0552]
_cell_length_c [12.3970]
_cell_angle_alpha [90.0000]
_cell_angle_beta [90.0000]
_cell_angle_gamma [90.0000]
_symmetry_Int_Tables_number [44]
_chemical_formula_structural [K2MgCu]
_chemical_formula_sum '[K4 Mg2 Cu2]'
_cell_volume [293.8028]
_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
[
  K  K0  2  0.0000  0.0000  0.0470  1
  K  K1  2  0.0000  0.5000  0.2380  1
  Mg  Mg2  2  0.0000  0.0000  0.4286  1
  Cu  Cu3  2  0.0000  0.5000  0.7864  1
]