data_CuSiSe2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   7.02
_cell_length_b   7.02
_cell_length_c   3.6
_cell_angle_alpha   98.91
_cell_angle_beta   98.91
_cell_angle_gamma   29.82
_symmetry_Int_Tables_number   1
_chemical_formula_structural   CuSiSe2
_chemical_formula_sum   'Cu1 Si1 Se2'
_cell_volume   87.14
_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  0.73  0.0  0.64  1.0
  Si  Si3  1  0.17  0.0  0.05  1.0
  Se  Se1  1  0.09  0.0  0.17  1.0
  Se  Se2  1  0.51  0.0  0.46  1.0

data_CuSiSe2
_symmetry_space_group_name_H-M   P1
_cell_length_a   3.6
_cell_length_b   3.61
_cell_length_c   7.02
_cell_angle_alpha   104.91
_cell_angle_beta   98.91
_cell_angle_gamma   90.0
_symmetry_Int_Tables_number   1
_chemical_formula_structural   CuSiSe2
_chemical_formula_sum   'Cu1 Si1 Se2'
_cell_volume   87.14
_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  0.36  0.0  0.27  1.0
  Si  Si1  1  0.95  0.0  0.83  1.0
  Se  Se2  1  0.54  0.0  0.49  1.0
  Se  Se3  1  0.83  0.0  0.91  1.0

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