data_[Ca9Mg21Cu6]
loop_
 _atom_type_symbol
 _atom_type_electronegativity
 _atom_type_radius
 _atom_type_ionic_radius
[
  Ca  1.0000  1.8000  1.1400
  Mg  1.3100  1.5000  0.8600
  Cu  1.9000  1.3500  0.8200
]
_symmetry_space_group_name_H-M [R-3m]
_cell_length_a [6.0553]
_cell_length_b [6.0553]
_cell_length_c [28.0437]
_cell_angle_alpha [90.0000]
_cell_angle_beta [90.0000]
_cell_angle_gamma [120.0000]
_symmetry_Int_Tables_number [166]
_chemical_formula_structural [Ca3Mg7Cu2]
_chemical_formula_sum '[Ca9 Mg21 Cu6]'
_cell_volume [890.4950]
_cell_formula_units_Z [3]
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  6  0.0000  0.0000  0.1438  1.0
  Ca  Ca1  3  0.0000  0.0000  0.0000  1.0
  Mg  Mg2  18  0.0018  0.5009  0.9262  1.0
  Mg  Mg3  3  -0.0000  -0.0000  0.5000  1.0
  Cu  Cu4  6  0.0000  0.0000  0.3333  1.0
]