data_Mn(CdSe)2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.71
_cell_length_b   5.71
_cell_length_c   5.71
_cell_angle_alpha   124.43
_cell_angle_beta   124.43
_cell_angle_gamma   82.48
_symmetry_Int_Tables_number   1
_chemical_formula_structural   Mn(CdSe)2
_chemical_formula_sum   'Mn1 Cd2 Se2'
_cell_volume   121.52
_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
  Mn  Mn2  1  0.0  0.0  0.0  1.0
  Cd  Cd0  1  0.0  0.0  0.66  1.0
  Cd  Cd1  1  0.0  0.0  0.93  1.0
  Se  Se3  1  0.0  0.66  0.15  1.0
  Se  Se4  1  0.66  0.0  0.15  1.0

data_Mn(CdSe)2
_symmetry_space_group_name_H-M   Cm
_cell_length_a   7.53
_cell_length_b   7.53
_cell_length_c   5.71
_cell_angle_alpha   90.0
_cell_angle_beta   131.24
_cell_angle_gamma   90.0
_symmetry_Int_Tables_number   8
_chemical_formula_structural   Mn(CdSe)2
_chemical_formula_sum   'Mn2 Cd4 Se4'
_cell_volume   243.05
_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
  Mn  Mn0  2  0.0  0.0  0.0  1.0
  Cd  Cd1  2  0.0  0.0  0.66  1.0
  Cd  Cd2  2  0.0  0.0  0.93  1.0
  Se  Se3  4  0.17  0.17  0.49  1.0

Mn Cd Cd Se Se
Mn(CdSe)2 crystallizes in the monoclinic Cm space group. Mn(1) is bonded in a distorted single-bond geometry to one Cd(2) and two equivalent Se(1) atoms. The Mn(1)-Cd(2) bond length is 0.43 Å. Both Mn(1)-Se(1) bond lengths are 2.50 Å. There are two inequivalent Cd sites. In the first Cd site, Cd(1) is bonded in a 5-coordinate geometry to one Cd(2) and four equivalent Se(1) atoms. The Cd(1)-Cd(2) bond length is 1.53 Å. There are two shorter (2.43 Å) and two longer (3.18 Å) Cd(1)-Se(1) bond lengths. In the second Cd site, Cd(2) is bonded in a distorted single-bond geometry to one Mn(1) and one Cd(1) atom. Se(1) is bonded in a 2-coordinate geometry to one Mn(1) and two equivalent Cd(1) atoms.