The structure described by Cr3TlSe5 crystallizes in the monoclinic C2/m space group. There are four inequivalent Cr sites. In the first Cr site, Cr(1) is bonded to two equivalent Se(2) and four equivalent Se(1) atoms to form a mixture of edge and corner-sharing CrSe6 octahedra. The corner-sharing octahedral tilt angles are 49°. In the second Cr site, Cr(2) is bonded to two equivalent Se(3) and four equivalent Se(5) atoms to form a mixture of edge and corner-sharing CrSe6 octahedra. The corner-sharing octahedral tilt angles are 50°. In the third Cr site, Cr(3) is bonded to one Se(1), two equivalent Se(3), and three equivalent Se(4) atoms to form a mixture of edge, face, and corner-sharing CrSe6 octahedra. The corner-sharing octahedral tilt angles range from 48-50°. In the fourth Cr site, Cr(4) is bonded to one Se(1), one Se(5), two equivalent Se(2), and two equivalent Se(3) atoms to form a mixture of edge, face, and corner-sharing CrSe6 octahedra. The corner-sharing octahedral tilt angles are 48°. Tl(1) is bonded in a 4-coordinate geometry to two equivalent Se(4) and two equivalent Se(5) atoms. There are five inequivalent Se sites. In the first Se site, Se(1) is bonded in a rectangular see-saw-like geometry to one Cr(3), one Cr(4), and two equivalent Cr(1) atoms. In the second Se site, Se(2) is bonded in a distorted T-shaped geometry to one Cr(1) and two equivalent Cr(4) atoms. In the third Se site, Se(3) is bonded to one Cr(2), two equivalent Cr(3), and two equivalent Cr(4) atoms to form a mixture of distorted edge and corner-sharing SeCr5 square pyramids. In the fourth Se site, Se(4) is bonded in a 3-coordinate geometry to three equivalent Cr(3) and two equivalent Tl(1) atoms. In the fifth Se site, Se(5) is bonded in a 3-coordinate geometry to one Cr(4), two equivalent Cr(2), and two equivalent Tl(1) atoms. is represented by the CIF file [CIF]
data_TlCr3Se5
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   10.353
_cell_length_b   10.353
_cell_length_c   12.734
_cell_angle_alpha   58.190
_cell_angle_beta   58.190
_cell_angle_gamma   20.638
_symmetry_Int_Tables_number   1
_cell_volume   406.219
_cell_formula_units_Z   2
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
  Tl  Tl0  1  0.261  0.261  0.828  1.0
  Tl  Tl1  1  0.739  0.739  0.172  1.0
  Cr  Cr2  1  0.500  0.500  0.000  1.0
  Cr  Cr3  1  0.500  0.500  0.500  1.0
  Cr  Cr4  1  0.164  0.164  0.612  1.0
  Cr  Cr5  1  0.836  0.836  0.388  1.0
  Cr  Cr6  1  0.985  0.985  0.772  1.0
  Cr  Cr7  1  0.015  0.015  0.228  1.0
  Se  Se8  1  0.079  0.079  0.849  1.0
  Se  Se9  1  0.921  0.921  0.151  1.0
  Se  Se10  1  0.409  0.409  0.919  1.0
  Se  Se11  1  0.591  0.591  0.081  1.0
  Se  Se12  1  0.577  0.577  0.606  1.0
  Se  Se13  1  0.423  0.423  0.394  1.0
  Se  Se14  1  0.746  0.746  0.620  1.0
  Se  Se15  1  0.254  0.254  0.380  1.0
  Se  Se16  1  0.919  0.919  0.654  1.0
  Se  Se17  1  0.081  0.081  0.346  1.0
[/CIF]
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The structure described by Cr3TlSe5 crystallizes in the monoclinic C2/m space group. There are four inequivalent Cr sites. In the first Cr site, Cr(1) is bonded to two equivalent Se(2) and four equivalent Se(1) atoms to form a mixture of edge and corner-sharing CrSe6 octahedra. The corner-sharing octahedral tilt angles are 49°. In the second Cr site, Cr(2) is bonded to two equivalent Se(3) and four equivalent Se(5) atoms to form a mixture of edge and corner-sharing CrSe6 octahedra. The corner-sharing octahedral tilt angles are 50°. In the third Cr site, Cr(3) is bonded to one Se(1), two equivalent Se(3), and three equivalent Se(4) atoms to form a mixture of edge, face, and corner-sharing CrSe6 octahedra. The corner-sharing octahedral tilt angles range from 48-50°. In the fourth Cr site, Cr(4) is bonded to one Se(1), one Se(5), two equivalent Se(2), and two equivalent Se(3) atoms to form a mixture of edge, face, and corner-sharing CrSe6 octahedra. The corner-sharing octahedral tilt angles are 48°. Tl(1) is bonded in a 4-coordinate geometry to two equivalent Se(4) and two equivalent Se(5) atoms. There are five inequivalent Se sites. In the first Se site, Se(1) is bonded in a rectangular see-saw-like geometry to one Cr(3), one Cr(4), and two equivalent Cr(1) atoms. In the second Se site, Se(2) is bonded in a distorted T-shaped geometry to one Cr(1) and two equivalent Cr(4) atoms. In the third Se site, Se(3) is bonded to one Cr(2), two equivalent Cr(3), and two equivalent Cr(4) atoms to form a mixture of distorted edge and corner-sharing SeCr5 square pyramids. In the fourth Se site, Se(4) is bonded in a 3-coordinate geometry to three equivalent Cr(3) and two equivalent Tl(1) atoms. In the fifth Se site, Se(5) is bonded in a 3-coordinate geometry to one Cr(4), two equivalent Cr(2), and two equivalent Tl(1) atoms. is represented by the CIF file [CIF]
data_TlCr3Se5
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   10.353
_cell_length_b   10.353
_cell_length_c   12.734
_cell_angle_alpha   58.190
_cell_angle_beta   58.190
_cell_angle_gamma   20.638
_symmetry_Int_Tables_number   1
_cell_volume   406.219
_cell_formula_units_Z   2
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
  Tl  Tl0  1  0.261  0.261  0.828  1.0
  Tl  Tl1  1  0.739  0.739  0.172  1.0
  Cr  Cr2  1  0.500  0.500  0.000  1.0
  Cr  Cr3  1  0.500  0.500  0.500  1.0
  Cr  Cr4  1  0.164  0.164  0.612  1.0
  Cr  Cr5  1  0.836  0.836  0.388  1.0
  Cr  Cr6  1  0.985  0.985  0.772  1.0
  Cr  Cr7  1  0.015  0.015  0.228  1.0
  Se  Se8  1  0.079  0.079  0.849  1.0
  Se  Se9  1  0.921  0.921  0.151  1.0
  Se  Se10  1  0.409  0.409  0.919  1.0
  Se  Se11  1  0.591  0.591  0.081  1.0
  Se  Se12  1  0.577  0.577  0.606  1.0
  Se  Se13  1  0.423  0.423  0.394  1.0
  Se  Se14  1  0.746  0.746  0.620  1.0
  Se  Se15  1  0.254  0.254  0.380  1.0
  Se  Se16  1  0.919  0.919  0.654  1.0
  Se  Se17  1  0.081  0.081  0.346  1.0
[/CIF]
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