The material structure described by Lu3Cu5Tl2Se8 crystallizes in the monoclinic Cm space group. There are three inequivalent Lu sites. In the first Lu site, Lu(1) is bonded to one Se(5), one Se(8), two equivalent Se(6), and two equivalent Se(7) atoms to form LuSe6 octahedra that share corners with four equivalent Cu(4)Se4 tetrahedra, edges with two equivalent Lu(1)Se6 octahedra, edges with two equivalent Lu(2)Se6 octahedra,  an edgeedge with one Cu(4)Se4 tetrahedra, edges with two equivalent Cu(2)Se4 tetrahedra, and edges with two equivalent Cu(5)Se4 tetrahedra. In the second Lu site, Lu(2) is bonded to one Se(2), one Se(7), two equivalent Se(3), and two equivalent Se(8) atoms to form LuSe6 octahedra that share corners with four equivalent Cu(5)Se4 tetrahedra, edges with two equivalent Lu(1)Se6 octahedra, edges with two equivalent Lu(2)Se6 octahedra,  an edgeedge with one Cu(5)Se4 tetrahedra, edges with two equivalent Cu(1)Se4 tetrahedra, and edges with two equivalent Cu(4)Se4 tetrahedra. In the third Lu site, Lu(3) is bonded in a 6-coordinate geometry to one Cu(3), one Se(2), one Se(5), two equivalent Se(1), and two equivalent Se(4) atoms. There are five inequivalent Cu sites. In the first Cu site, Cu(1) is bonded to one Se(1), one Se(3), and two equivalent Se(2) atoms to form CuSe4 tetrahedra that share  a cornercorner with one Cu(4)Se4 tetrahedra,  a cornercorner with one Cu(5)Se4 tetrahedra, corners with two equivalent Cu(1)Se4 tetrahedra, and edges with two equivalent Lu(2)Se6 octahedra. In the second Cu site, Cu(2) is bonded to one Se(4), one Se(6), and two equivalent Se(5) atoms to form CuSe4 tetrahedra that share  a cornercorner with one Cu(4)Se4 tetrahedra,  a cornercorner with one Cu(5)Se4 tetrahedra, corners with two equivalent Cu(2)Se4 tetrahedra, and edges with two equivalent Lu(1)Se6 octahedra. In the third Cu site, Cu(3) is bonded in a 8-coordinate geometry to one Lu(3), one Tl(1), two equivalent Tl(2), one Se(4), one Se(5), and two equivalent Se(1) atoms. In the fourth Cu site, Cu(4) is bonded to one Se(3), one Se(6), and two equivalent Se(7) atoms to form distorted CuSe4 tetrahedra that share corners with four equivalent Lu(1)Se6 octahedra,  a cornercorner with one Cu(1)Se4 tetrahedra,  a cornercorner with one Cu(2)Se4 tetrahedra, corners with two equivalent Cu(4)Se4 tetrahedra,  an edgeedge with one Lu(1)Se6 octahedra, edges with two equivalent Lu(2)Se6 octahedra, and  an edgeedge with one Cu(5)Se4 tetrahedra. The corner-sharing octahedral tilt angles range from 15-61°. In the fifth Cu site, Cu(5) is bonded to one Se(3), one Se(6), and two equivalent Se(8) atoms to form distorted CuSe4 tetrahedra that share corners with four equivalent Lu(2)Se6 octahedra,  a cornercorner with one Cu(1)Se4 tetrahedra,  a cornercorner with one Cu(2)Se4 tetrahedra, corners with two equivalent Cu(5)Se4 tetrahedra,  an edgeedge with one Lu(2)Se6 octahedra, edges with two equivalent Lu(1)Se6 octahedra, and  an edgeedge with one Cu(4)Se4 tetrahedra. The corner-sharing octahedral tilt angles range from 15-61°. There are two inequivalent Tl sites. In the first Tl site, Tl(1) is bonded in a 4-coordinate geometry to one Cu(3), one Se(8), and two equivalent Se(2) atoms. In the second Tl site, Tl(2) is bonded in a 1-coordinate geometry to two equivalent Cu(3) and one Se(7) atom. There are eight inequivalent Se sites. In the first Se site, Se(1) is bonded in a 5-coordinate geometry to two equivalent Lu(3), one Cu(1), and two equivalent Cu(3) atoms. In the second Se site, Se(2) is bonded in a 6-coordinate geometry to one Lu(2), one Lu(3), two equivalent Cu(1), and two equivalent Tl(1) atoms. In the third Se site, Se(3) is bonded in a distorted pentagonal planar geometry to two equivalent Lu(2), one Cu(1), one Cu(4), and one Cu(5) atom. In the fourth Se site, Se(4) is bonded in a 4-coordinate geometry to two equivalent Lu(3), one Cu(2), and one Cu(3) atom. In the fifth Se site, Se(5) is bonded in a 5-coordinate geometry to one Lu(1), one Lu(3), one Cu(3), and two equivalent Cu(2) atoms. In the sixth Se site, Se(6) is bonded in a distorted pentagonal planar geometry to two equivalent Lu(1), one Cu(2), one Cu(4), and one Cu(5) atom. In the seventh Se site, Se(7) is bonded to one Lu(2), two equivalent Lu(1), two equivalent Cu(4), and one Tl(2) atom to form distorted edge-sharing SeLu3TlCu2 octahedra. In the eighth Se site, Se(8) is bonded in a 6-coordinate geometry to one Lu(1), two equivalent Lu(2), two equivalent Cu(5), and one Tl(1) atom. is represented by the CIF file [CIF]
data_Lu3Tl2Cu5Se8
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   7.443
_cell_length_b   7.443
_cell_length_c   14.697
_cell_angle_alpha   70.242
_cell_angle_beta   70.242
_cell_angle_gamma   31.693
_symmetry_Int_Tables_number   1
_cell_volume   400.451
_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
  Lu  Lu0  1  0.035  0.035  0.593  1.0
  Lu  Lu1  1  0.336  0.336  0.826  1.0
  Lu  Lu2  1  0.200  0.200  0.210  1.0
  Tl  Tl3  1  0.009  0.009  0.010  1.0
  Tl  Tl4  1  0.359  0.359  0.415  1.0
  Cu  Cu5  1  0.728  0.728  0.017  1.0
  Cu  Cu6  1  0.652  0.652  0.401  1.0
  Cu  Cu7  1  0.983  0.983  0.241  1.0
  Cu  Cu8  1  0.784  0.784  0.672  1.0
  Cu  Cu9  1  0.588  0.588  0.749  1.0
  Se  Se10  1  0.578  0.578  0.165  1.0
  Se  Se11  1  0.325  0.325  0.017  1.0
  Se  Se12  1  0.694  0.694  0.853  1.0
  Se  Se13  1  0.808  0.808  0.258  1.0
  Se  Se14  1  0.053  0.053  0.397  1.0
  Se  Se15  1  0.677  0.677  0.567  1.0
  Se  Se16  1  0.387  0.387  0.623  1.0
  Se  Se17  1  0.986  0.986  0.795  1.0
[/CIF]
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The material structure described by Lu3Cu5Tl2Se8 crystallizes in the monoclinic Cm space group. There are three inequivalent Lu sites. In the first Lu site, Lu(1) is bonded to one Se(5), one Se(8), two equivalent Se(6), and two equivalent Se(7) atoms to form LuSe6 octahedra that share corners with four equivalent Cu(4)Se4 tetrahedra, edges with two equivalent Lu(1)Se6 octahedra, edges with two equivalent Lu(2)Se6 octahedra,  an edgeedge with one Cu(4)Se4 tetrahedra, edges with two equivalent Cu(2)Se4 tetrahedra, and edges with two equivalent Cu(5)Se4 tetrahedra. In the second Lu site, Lu(2) is bonded to one Se(2), one Se(7), two equivalent Se(3), and two equivalent Se(8) atoms to form LuSe6 octahedra that share corners with four equivalent Cu(5)Se4 tetrahedra, edges with two equivalent Lu(1)Se6 octahedra, edges with two equivalent Lu(2)Se6 octahedra,  an edgeedge with one Cu(5)Se4 tetrahedra, edges with two equivalent Cu(1)Se4 tetrahedra, and edges with two equivalent Cu(4)Se4 tetrahedra. In the third Lu site, Lu(3) is bonded in a 6-coordinate geometry to one Cu(3), one Se(2), one Se(5), two equivalent Se(1), and two equivalent Se(4) atoms. There are five inequivalent Cu sites. In the first Cu site, Cu(1) is bonded to one Se(1), one Se(3), and two equivalent Se(2) atoms to form CuSe4 tetrahedra that share  a cornercorner with one Cu(4)Se4 tetrahedra,  a cornercorner with one Cu(5)Se4 tetrahedra, corners with two equivalent Cu(1)Se4 tetrahedra, and edges with two equivalent Lu(2)Se6 octahedra. In the second Cu site, Cu(2) is bonded to one Se(4), one Se(6), and two equivalent Se(5) atoms to form CuSe4 tetrahedra that share  a cornercorner with one Cu(4)Se4 tetrahedra,  a cornercorner with one Cu(5)Se4 tetrahedra, corners with two equivalent Cu(2)Se4 tetrahedra, and edges with two equivalent Lu(1)Se6 octahedra. In the third Cu site, Cu(3) is bonded in a 8-coordinate geometry to one Lu(3), one Tl(1), two equivalent Tl(2), one Se(4), one Se(5), and two equivalent Se(1) atoms. In the fourth Cu site, Cu(4) is bonded to one Se(3), one Se(6), and two equivalent Se(7) atoms to form distorted CuSe4 tetrahedra that share corners with four equivalent Lu(1)Se6 octahedra,  a cornercorner with one Cu(1)Se4 tetrahedra,  a cornercorner with one Cu(2)Se4 tetrahedra, corners with two equivalent Cu(4)Se4 tetrahedra,  an edgeedge with one Lu(1)Se6 octahedra, edges with two equivalent Lu(2)Se6 octahedra, and  an edgeedge with one Cu(5)Se4 tetrahedra. The corner-sharing octahedral tilt angles range from 15-61°. In the fifth Cu site, Cu(5) is bonded to one Se(3), one Se(6), and two equivalent Se(8) atoms to form distorted CuSe4 tetrahedra that share corners with four equivalent Lu(2)Se6 octahedra,  a cornercorner with one Cu(1)Se4 tetrahedra,  a cornercorner with one Cu(2)Se4 tetrahedra, corners with two equivalent Cu(5)Se4 tetrahedra,  an edgeedge with one Lu(2)Se6 octahedra, edges with two equivalent Lu(1)Se6 octahedra, and  an edgeedge with one Cu(4)Se4 tetrahedra. The corner-sharing octahedral tilt angles range from 15-61°. There are two inequivalent Tl sites. In the first Tl site, Tl(1) is bonded in a 4-coordinate geometry to one Cu(3), one Se(8), and two equivalent Se(2) atoms. In the second Tl site, Tl(2) is bonded in a 1-coordinate geometry to two equivalent Cu(3) and one Se(7) atom. There are eight inequivalent Se sites. In the first Se site, Se(1) is bonded in a 5-coordinate geometry to two equivalent Lu(3), one Cu(1), and two equivalent Cu(3) atoms. In the second Se site, Se(2) is bonded in a 6-coordinate geometry to one Lu(2), one Lu(3), two equivalent Cu(1), and two equivalent Tl(1) atoms. In the third Se site, Se(3) is bonded in a distorted pentagonal planar geometry to two equivalent Lu(2), one Cu(1), one Cu(4), and one Cu(5) atom. In the fourth Se site, Se(4) is bonded in a 4-coordinate geometry to two equivalent Lu(3), one Cu(2), and one Cu(3) atom. In the fifth Se site, Se(5) is bonded in a 5-coordinate geometry to one Lu(1), one Lu(3), one Cu(3), and two equivalent Cu(2) atoms. In the sixth Se site, Se(6) is bonded in a distorted pentagonal planar geometry to two equivalent Lu(1), one Cu(2), one Cu(4), and one Cu(5) atom. In the seventh Se site, Se(7) is bonded to one Lu(2), two equivalent Lu(1), two equivalent Cu(4), and one Tl(2) atom to form distorted edge-sharing SeLu3TlCu2 octahedra. In the eighth Se site, Se(8) is bonded in a 6-coordinate geometry to one Lu(1), two equivalent Lu(2), two equivalent Cu(5), and one Tl(1) atom. is represented by the CIF file [CIF]
data_Lu3Tl2Cu5Se8
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   7.443
_cell_length_b   7.443
_cell_length_c   14.697
_cell_angle_alpha   70.242
_cell_angle_beta   70.242
_cell_angle_gamma   31.693
_symmetry_Int_Tables_number   1
_cell_volume   400.451
_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
  Lu  Lu0  1  0.035  0.035  0.593  1.0
  Lu  Lu1  1  0.336  0.336  0.826  1.0
  Lu  Lu2  1  0.200  0.200  0.210  1.0
  Tl  Tl3  1  0.009  0.009  0.010  1.0
  Tl  Tl4  1  0.359  0.359  0.415  1.0
  Cu  Cu5  1  0.728  0.728  0.017  1.0
  Cu  Cu6  1  0.652  0.652  0.401  1.0
  Cu  Cu7  1  0.983  0.983  0.241  1.0
  Cu  Cu8  1  0.784  0.784  0.672  1.0
  Cu  Cu9  1  0.588  0.588  0.749  1.0
  Se  Se10  1  0.578  0.578  0.165  1.0
  Se  Se11  1  0.325  0.325  0.017  1.0
  Se  Se12  1  0.694  0.694  0.853  1.0
  Se  Se13  1  0.808  0.808  0.258  1.0
  Se  Se14  1  0.053  0.053  0.397  1.0
  Se  Se15  1  0.677  0.677  0.567  1.0
  Se  Se16  1  0.387  0.387  0.623  1.0
  Se  Se17  1  0.986  0.986  0.795  1.0
[/CIF]
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