data_Sr(CdSe)2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   6.16
_cell_length_b   6.16
_cell_length_c   6.16
_cell_angle_alpha   129.41
_cell_angle_beta   129.41
_cell_angle_gamma   74.36
_symmetry_Int_Tables_number   1
_chemical_formula_structural   Sr(CdSe)2
_chemical_formula_sum   'Sr1 Cd2 Se2'
_cell_volume   136.18
_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
  Sr  Sr4  1  0.0  0.0  0.0  1.0
  Cd  Cd0  1  0.0  0.0  0.25  1.0
  Cd  Cd1  1  0.0  0.0  0.57  1.0
  Se  Se2  1  0.0  0.63  0.46  1.0
  Se  Se3  1  0.63  0.0  0.46  1.0

data_Sr(CdSe)2
_symmetry_space_group_name_H-M   Cm
_cell_length_a   7.45
_cell_length_b   7.45
_cell_length_c   6.16
_cell_angle_alpha   90.0
_cell_angle_beta   127.18
_cell_angle_gamma   90.0
_symmetry_Int_Tables_number   8
_chemical_formula_structural   Sr(CdSe)2
_chemical_formula_sum   'Sr2 Cd4 Se4'
_cell_volume   272.36
_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
  Sr  Sr0  2  0.0  0.0  0.0  1.0
  Cd  Cd1  2  0.0  0.0  0.25  1.0
  Cd  Cd2  2  0.0  0.0  0.57  1.0
  Se  Se3  4  0.18  0.18  0.82  1.0

Sr Cd Cd Se Se