data_MgFe2Cu
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   3.55
_cell_length_b   3.69
_cell_length_c   4.03
_cell_angle_alpha   90.0
_cell_angle_beta   90.0
_cell_angle_gamma   90.0
_symmetry_Int_Tables_number   1
_chemical_formula_structural   MgFe2Cu
_chemical_formula_sum   'Mg1 Fe2 Cu1'
_cell_volume   52.94
_cell_formula_units_Z   1
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  Mg3  1  0.0  0.0  0.0  1.0
  Fe  Fe1  1  0.78  0.0  0.02  1.0
  Fe  Fe2  1  0.0  0.85  0.02  1.0
  Cu  Cu0  1  0.78  0.85  0.0  1.0

data_MgFe2Cu
_symmetry_space_group_name_H-M   P1
_cell_length_a   3.55
_cell_length_b   3.69
_cell_length_c   4.03
_cell_angle_alpha   90.0
_cell_angle_beta   90.0
_cell_angle_gamma   90.0
_symmetry_Int_Tables_number   1
_chemical_formula_structural   MgFe2Cu
_chemical_formula_sum   'Mg1 Fe2 Cu1'
_cell_volume   52.94
_cell_formula_units_Z   1
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  0.0  0.0  0.0  1.0
  Fe  Fe1  1  -0.0  0.85  0.02  1.0
  Fe  Fe2  1  0.78  0.0  0.02  1.0
  Cu  Cu3  1  0.78  0.85  0.0  1.0

Mg Fe Fe Cu
Mg Fe Fe Cu 0 2 o - o 1 3 o - o 