data_As2SeBr
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   3.63
_cell_length_b   3.63
_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   As2SeBr
_chemical_formula_sum   'As2 Se1 Br1'
_cell_volume   96.4
_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
  As  As0  1  0.81  0.81  0.26  1.0
  As  As1  1  0.0  0.0  0.27  1.0
  Se  Se3  1  0.0  0.0  0.08  1.0
  Br  Br2  1  0.81  0.81  0.39  1.0

data_As2SeBr
_symmetry_space_group_name_H-M   Cm
_cell_length_a   5.13
_cell_length_b   5.13
_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   As2SeBr
_chemical_formula_sum   'As4 Se2 Br2'
_cell_volume   192.79
_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
  As  As0  2  0.0  0.0  0.27  1.0
  As  As1  2  0.31  0.5  0.26  1.0
  Se  Se2  2  0.0  0.0  0.08  1.0
  Br  Br3  2  0.31  0.5  0.39  1.0

As As Se Br
As2SeBr is Indium-like structured and crystallizes in the monoclinic Cm space group. The structure is zero-dimensional and consists of two As2SeBr clusters. There are two inequivalent As sites. In the first As site, As(1) is bonded in a distorted single-bond geometry to one As(2), one Se(1), and one Br(1) atom. The As(1)-As(2) bond length is 0.97 Å. The As(1)-Se(1) bond length is 1.59 Å. The As(1)-Br(1) bond length is 1.02 Å. In the second As site, As(2) is bonded in a 3-coordinate geometry to one As(1), one Se(1), and one Br(1) atom. The As(2)-Se(1) bond length is 1.37 Å. The As(2)-Br(1) bond length is 1.32 Å. Se(1) is bonded in a 2-coordinate geometry to one As(1) and one As(2) atom. Br(1) is bonded in a distorted single-bond geometry to one As(1) and one As(2) atom.