The structure described by Cr5Se8 is beta indium sulfide-like structured and crystallizes in the monoclinic C2/m space group. There are three inequivalent Cr sites. In the first Cr site, Cr(1) is bonded to two equivalent Se(1) and four equivalent Se(3) atoms to form a mixture of face and corner-sharing CrSe6 octahedra. The corner-sharing octahedral tilt angles range from 49-52°. In the second Cr site, Cr(2) is bonded to one Se(1), one Se(2), and four equivalent Se(3) atoms to form a mixture of edge, face, and corner-sharing CrSe6 octahedra. The corner-sharing octahedral tilt angles are 52°. In the third Cr site, Cr(3) is bonded to two equivalent Se(1), two equivalent Se(2), and two equivalent Se(3) atoms to form a mixture of edge and corner-sharing CrSe6 octahedra. The corner-sharing octahedral tilt angles range from 49-50°. There are three inequivalent Se sites. In the first Se site, Se(1) is bonded to one Cr(1), one Cr(2), and two equivalent Cr(3) atoms to form a mixture of edge and corner-sharing SeCr4 trigonal pyramids. In the second Se site, Se(2) is bonded in a distorted T-shaped geometry to one Cr(2) and two equivalent Cr(3) atoms. In the third Se site, Se(3) is bonded in a rectangular see-saw-like geometry to one Cr(1), one Cr(3), and two equivalent Cr(2) atoms. is represented by the CIF file [CIF]
data_Cr5Se8
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   6.874
_cell_length_b   6.874
_cell_length_c   7.257
_cell_angle_alpha   104.443
_cell_angle_beta   106.080
_cell_angle_gamma   116.369
_symmetry_Int_Tables_number   1
_cell_volume   266.138
_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
  Cr  Cr0  1  0.000  0.000  0.000  1.0
  Cr  Cr1  1  0.260  0.730  0.990  1.0
  Cr  Cr2  1  0.740  0.270  0.010  1.0
  Cr  Cr3  1  0.770  0.270  0.500  1.0
  Cr  Cr4  1  0.230  0.730  0.500  1.0
  Se  Se5  1  0.300  0.022  0.322  1.0
  Se  Se6  1  0.700  0.978  0.678  1.0
  Se  Se7  1  0.787  0.546  0.333  1.0
  Se  Se8  1  0.213  0.454  0.667  1.0
  Se  Se9  1  0.198  0.454  0.170  1.0
  Se  Se10  1  0.716  0.972  0.170  1.0
  Se  Se11  1  0.802  0.546  0.830  1.0
  Se  Se12  1  0.284  0.028  0.830  1.0
[/CIF]
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The structure described by Cr5Se8 is beta indium sulfide-like structured and crystallizes in the monoclinic C2/m space group. There are three inequivalent Cr sites. In the first Cr site, Cr(1) is bonded to two equivalent Se(1) and four equivalent Se(3) atoms to form a mixture of face and corner-sharing CrSe6 octahedra. The corner-sharing octahedral tilt angles range from 49-52°. In the second Cr site, Cr(2) is bonded to one Se(1), one Se(2), and four equivalent Se(3) atoms to form a mixture of edge, face, and corner-sharing CrSe6 octahedra. The corner-sharing octahedral tilt angles are 52°. In the third Cr site, Cr(3) is bonded to two equivalent Se(1), two equivalent Se(2), and two equivalent Se(3) atoms to form a mixture of edge and corner-sharing CrSe6 octahedra. The corner-sharing octahedral tilt angles range from 49-50°. There are three inequivalent Se sites. In the first Se site, Se(1) is bonded to one Cr(1), one Cr(2), and two equivalent Cr(3) atoms to form a mixture of edge and corner-sharing SeCr4 trigonal pyramids. In the second Se site, Se(2) is bonded in a distorted T-shaped geometry to one Cr(2) and two equivalent Cr(3) atoms. In the third Se site, Se(3) is bonded in a rectangular see-saw-like geometry to one Cr(1), one Cr(3), and two equivalent Cr(2) atoms. is represented by the CIF file [CIF]
data_Cr5Se8
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   6.874
_cell_length_b   6.874
_cell_length_c   7.257
_cell_angle_alpha   104.443
_cell_angle_beta   106.080
_cell_angle_gamma   116.369
_symmetry_Int_Tables_number   1
_cell_volume   266.138
_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
  Cr  Cr0  1  0.000  0.000  0.000  1.0
  Cr  Cr1  1  0.260  0.730  0.990  1.0
  Cr  Cr2  1  0.740  0.270  0.010  1.0
  Cr  Cr3  1  0.770  0.270  0.500  1.0
  Cr  Cr4  1  0.230  0.730  0.500  1.0
  Se  Se5  1  0.300  0.022  0.322  1.0
  Se  Se6  1  0.700  0.978  0.678  1.0
  Se  Se7  1  0.787  0.546  0.333  1.0
  Se  Se8  1  0.213  0.454  0.667  1.0
  Se  Se9  1  0.198  0.454  0.170  1.0
  Se  Se10  1  0.716  0.972  0.170  1.0
  Se  Se11  1  0.802  0.546  0.830  1.0
  Se  Se12  1  0.284  0.028  0.830  1.0
[/CIF]
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