data_Cu2PSe
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   2.9
_cell_length_b   2.9
_cell_length_c   7.33
_cell_angle_alpha   90.0
_cell_angle_beta   90.0
_cell_angle_gamma   90.0
_symmetry_Int_Tables_number   1
_chemical_formula_structural   Cu2PSe
_chemical_formula_sum   'Cu2 P1 Se1'
_cell_volume   61.75
_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
  Cu  Cu0  1  0.45  0.45  0.85  1.0
  Cu  Cu1  1  0.45  0.45  0.49  1.0
  P  P2  1  0.0  0.0  0.0  1.0
  Se  Se3  1  0.0  0.0  0.67  1.0

data_Cu2PSe
_symmetry_space_group_name_H-M   Cm
_cell_length_a   4.1
_cell_length_b   4.1
_cell_length_c   7.33
_cell_angle_alpha   90.0
_cell_angle_beta   90.0
_cell_angle_gamma   90.0
_symmetry_Int_Tables_number   8
_chemical_formula_structural   Cu2PSe
_chemical_formula_sum   'Cu4 P2 Se2'
_cell_volume   123.49
_cell_formula_units_Z   2
loop_
 _symmetry_equiv_pos_site_id
 _symmetry_equiv_pos_as_xyz
  1  'x, y, z'
  2  'x, -y, z'
  3  'x+1/2, y+1/2, z'
  4  'x+1/2, -y+1/2, 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
  Cu  Cu0  2  0.45  0.0  0.49  1.0
  Cu  Cu1  2  0.45  0.0  0.85  1.0
  P  P2  2  0.0  0.0  0.0  1.0
  Se  Se3  2  0.0  0.0  0.67  1.0

Cu Cu P Se
Cu Cu P Se 0 3 o o o 0 3 o + o 0 3 + o o 0 3 + + o 0 2 o o + 0 2 o + + 0 2 + o + 0 2 + + + 0 1 o o o 1 3 o o o 1 3 o + o 1 3 + o o 1 3 + + o 1 1 + o o 1 1 o + o 2 3 o o - 