The material structure described by TlCu7Se4 crystallizes in the monoclinic Cm space group. There are seven inequivalent Cu sites. In the first Cu site, Cu(1) is bonded in a 3-coordinate geometry to one Se(1) and two equivalent Se(3) atoms. In the second Cu site, Cu(2) is bonded in a 3-coordinate geometry to one Cu(6), one Se(2), and two equivalent Se(4) atoms. In the third Cu site, Cu(3) is bonded in a distorted trigonal planar geometry to one Se(3) and two equivalent Se(2) atoms. In the fourth Cu site, Cu(4) is bonded in a 3-coordinate geometry to two equivalent Cu(6), one Se(4), and two equivalent Se(1) atoms. In the fifth Cu site, Cu(5) is bonded in a 4-coordinate geometry to one Se(2), one Se(3), and two equivalent Se(1) atoms. In the sixth Cu site, Cu(6) is bonded in a 9-coordinate geometry to one Cu(2), two equivalent Cu(4), two equivalent Cu(7), one Se(1), one Se(3), and two equivalent Se(4) atoms. In the seventh Cu site, Cu(7) is bonded in a 4-coordinate geometry to two equivalent Cu(6), one Se(2), one Se(4), and two equivalent Se(3) atoms. Tl(1) is bonded in a distorted body-centered cubic geometry to two equivalent Se(1), two equivalent Se(2), two equivalent Se(3), and two equivalent Se(4) atoms. There are four inequivalent Se sites. In the first Se site, Se(1) is bonded in a 6-coordinate geometry to one Cu(1), one Cu(6), two equivalent Cu(4), two equivalent Cu(5), and two equivalent Tl(1) atoms. In the second Se site, Se(2) is bonded in a 5-coordinate geometry to one Cu(2), one Cu(5), one Cu(7), two equivalent Cu(3), and two equivalent Tl(1) atoms. In the third Se site, Se(3) is bonded in a 7-coordinate geometry to one Cu(3), one Cu(5), one Cu(6), two equivalent Cu(1), two equivalent Cu(7), and two equivalent Tl(1) atoms. In the fourth Se site, Se(4) is bonded in a 8-coordinate geometry to one Cu(4), one Cu(7), two equivalent Cu(2), two equivalent Cu(6), and two equivalent Tl(1) atoms. is represented by the Crystallographic Information File (CIF) [CIF]
data_TlCu7Se4
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   7.675
_cell_length_b   7.675
_cell_length_c   10.455
_cell_angle_alpha   47.252
_cell_angle_beta   47.252
_cell_angle_gamma   29.699
_symmetry_Int_Tables_number   1
_cell_volume   217.224
_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
  Tl  Tl0  1  0.003  0.003  0.998  1.0
  Cu  Cu1  1  0.024  0.024  0.602  1.0
  Cu  Cu2  1  0.977  0.977  0.398  1.0
  Cu  Cu3  1  0.368  0.368  0.651  1.0
  Cu  Cu4  1  0.626  0.626  0.349  1.0
  Cu  Cu5  1  0.680  0.680  0.533  1.0
  Cu  Cu6  1  0.213  0.213  0.116  1.0
  Cu  Cu7  1  0.782  0.782  0.894  1.0
  Se  Se8  1  0.248  0.248  0.325  1.0
  Se  Se9  1  0.760  0.760  0.670  1.0
  Se  Se10  1  0.434  0.434  0.814  1.0
  Se  Se11  1  0.563  0.563  0.188  1.0
[/CIF]
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The material structure described by TlCu7Se4 crystallizes in the monoclinic Cm space group. There are seven inequivalent Cu sites. In the first Cu site, Cu(1) is bonded in a 3-coordinate geometry to one Se(1) and two equivalent Se(3) atoms. In the second Cu site, Cu(2) is bonded in a 3-coordinate geometry to one Cu(6), one Se(2), and two equivalent Se(4) atoms. In the third Cu site, Cu(3) is bonded in a distorted trigonal planar geometry to one Se(3) and two equivalent Se(2) atoms. In the fourth Cu site, Cu(4) is bonded in a 3-coordinate geometry to two equivalent Cu(6), one Se(4), and two equivalent Se(1) atoms. In the fifth Cu site, Cu(5) is bonded in a 4-coordinate geometry to one Se(2), one Se(3), and two equivalent Se(1) atoms. In the sixth Cu site, Cu(6) is bonded in a 9-coordinate geometry to one Cu(2), two equivalent Cu(4), two equivalent Cu(7), one Se(1), one Se(3), and two equivalent Se(4) atoms. In the seventh Cu site, Cu(7) is bonded in a 4-coordinate geometry to two equivalent Cu(6), one Se(2), one Se(4), and two equivalent Se(3) atoms. Tl(1) is bonded in a distorted body-centered cubic geometry to two equivalent Se(1), two equivalent Se(2), two equivalent Se(3), and two equivalent Se(4) atoms. There are four inequivalent Se sites. In the first Se site, Se(1) is bonded in a 6-coordinate geometry to one Cu(1), one Cu(6), two equivalent Cu(4), two equivalent Cu(5), and two equivalent Tl(1) atoms. In the second Se site, Se(2) is bonded in a 5-coordinate geometry to one Cu(2), one Cu(5), one Cu(7), two equivalent Cu(3), and two equivalent Tl(1) atoms. In the third Se site, Se(3) is bonded in a 7-coordinate geometry to one Cu(3), one Cu(5), one Cu(6), two equivalent Cu(1), two equivalent Cu(7), and two equivalent Tl(1) atoms. In the fourth Se site, Se(4) is bonded in a 8-coordinate geometry to one Cu(4), one Cu(7), two equivalent Cu(2), two equivalent Cu(6), and two equivalent Tl(1) atoms. is represented by the Crystallographic Information File (CIF) [CIF]
data_TlCu7Se4
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   7.675
_cell_length_b   7.675
_cell_length_c   10.455
_cell_angle_alpha   47.252
_cell_angle_beta   47.252
_cell_angle_gamma   29.699
_symmetry_Int_Tables_number   1
_cell_volume   217.224
_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
  Tl  Tl0  1  0.003  0.003  0.998  1.0
  Cu  Cu1  1  0.024  0.024  0.602  1.0
  Cu  Cu2  1  0.977  0.977  0.398  1.0
  Cu  Cu3  1  0.368  0.368  0.651  1.0
  Cu  Cu4  1  0.626  0.626  0.349  1.0
  Cu  Cu5  1  0.680  0.680  0.533  1.0
  Cu  Cu6  1  0.213  0.213  0.116  1.0
  Cu  Cu7  1  0.782  0.782  0.894  1.0
  Se  Se8  1  0.248  0.248  0.325  1.0
  Se  Se9  1  0.760  0.760  0.670  1.0
  Se  Se10  1  0.434  0.434  0.814  1.0
  Se  Se11  1  0.563  0.563  0.188  1.0
[/CIF]
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