data_CuSi2Se
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   2.7
_cell_length_b   4.41
_cell_length_c   6.18
_cell_angle_alpha   90.0
_cell_angle_beta   96.6
_cell_angle_gamma   90.0
_symmetry_Int_Tables_number   1
_chemical_formula_structural   CuSi2Se
_chemical_formula_sum   'Cu1 Si2 Se1'
_cell_volume   73.32
_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  0.79  0.0  0.89  1.0
  Si  Si2  1  0.33  0.0  0.62  1.0
  Si  Si3  1  0.86  0.21  0.63  1.0
  Se  Se1  1  0.01  0.21  0.07  1.0

data_CuSi2Se
_symmetry_space_group_name_H-M   P1
_cell_length_a   2.7
_cell_length_b   4.41
_cell_length_c   6.18
_cell_angle_alpha   90.0
_cell_angle_beta   96.6
_cell_angle_gamma   90.0
_symmetry_Int_Tables_number   1
_chemical_formula_structural   CuSi2Se
_chemical_formula_sum   'Cu1 Si2 Se1'
_cell_volume   73.32
_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
  Si  Si0  1  0.33  0.0  0.62  1.0
  Cu  Cu1  1  0.79  0.0  0.89  1.0
  Si  Si2  1  0.86  0.21  0.63  1.0
  Se  Se3  1  0.01  0.21  0.07  1.0

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