data_MgCuSe
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   3.81
_cell_length_b   7.59
_cell_length_c   7.59
_cell_angle_alpha   121.67
_cell_angle_beta   90.0
_cell_angle_gamma   90.0
_symmetry_Int_Tables_number   1
_chemical_formula_structural   MgCuSe
_chemical_formula_sum   'Mg3 Cu3 Se3'
_cell_volume   186.66
_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
  Mg  Mg3  1  0.9  0.57  0.12  1.0
  Mg  Mg4  1  0.9  0.43  0.12  1.0
  Mg  Mg5  1  0.0  0.0  0.53  1.0
  Cu  Cu0  1  0.9  0.38  0.21  1.0
  Cu  Cu1  1  0.9  0.62  0.21  1.0
  Cu  Cu2  1  0.9  0.0  0.63  1.0
  Se  Se6  1  0.0  0.17  0.62  1.0
  Se  Se7  1  0.0  0.83  0.62  1.0
  Se  Se8  1  0.0  0.0  0.93  1.0

data_MgCuSe
_symmetry_space_group_name_H-M   P1
_cell_length_a   3.81
_cell_length_b   7.39
_cell_length_c   7.59
_cell_angle_alpha   119.16
_cell_angle_beta   90.0
_cell_angle_gamma   90.0
_symmetry_Int_Tables_number   1
_chemical_formula_structural   MgCuSe
_chemical_formula_sum   'Mg3 Cu3 Se3'
_cell_volume   186.66
_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
  Mg  Mg0  1  0.0  0.47  0.47  1.0
  Mg  Mg1  1  0.9  0.88  0.31  1.0
  Mg  Mg2  1  0.9  0.88  0.45  1.0
  Cu  Cu3  1  0.9  0.37  0.37  1.0
  Cu  Cu4  1  0.9  0.79  0.18  1.0
  Cu  Cu5  1  0.9  0.79  0.41  1.0
  Se  Se6  1  0.0  0.07  0.07  1.0
  Se  Se7  1  0.0  0.38  0.21  1.0
  Se  Se8  1  0.0  0.38  0.55  1.0

Mg Mg Mg Cu Cu Cu Se Se Se
Mg Mg Mg Cu Cu Cu Se Se Se 0 4 o o o 1 3 o o o 2 5 - o o 2 6 o o o 5 7 + - o 5 8 + o o 7 8 o + o 