The crystal structure described by Er2Cu3TlS5 crystallizes in the orthorhombic Cmcm space group. Er(1) is bonded to one S(1), two equivalent S(2), and three equivalent S(3) atoms to form ErS6 octahedra that share  a cornercorner with one Er(1)S6 octahedra, corners with four equivalent Cu(2)S4 tetrahedra, edges with four equivalent Er(1)S6 octahedra, edges with two equivalent Cu(1)S4 tetrahedra, and edges with three equivalent Cu(2)S4 tetrahedra. The corner-sharing octahedral tilt angles are 30°. There are two inequivalent Cu sites. In the first Cu site, Cu(1) is bonded to two equivalent S(1) and two equivalent S(2) atoms to form CuS4 tetrahedra that share corners with two equivalent Cu(1)S4 tetrahedra, corners with four equivalent Cu(2)S4 tetrahedra, and edges with four equivalent Er(1)S6 octahedra. In the second Cu site, Cu(2) is bonded to two equivalent S(2) and two equivalent S(3) atoms to form distorted CuS4 tetrahedra that share corners with four equivalent Er(1)S6 octahedra, corners with two equivalent Cu(1)S4 tetrahedra, corners with two equivalent Cu(2)S4 tetrahedra, edges with three equivalent Er(1)S6 octahedra, and  an edgeedge with one Cu(2)S4 tetrahedra. The corner-sharing octahedral tilt angles range from 14-60°. Tl(1) is bonded in a 4-coordinate geometry to two equivalent S(1) and two equivalent S(3) atoms. There are three inequivalent S sites. In the first S site, S(1) is bonded in a 4-coordinate geometry to two equivalent Er(1), two equivalent Cu(1), and two equivalent Tl(1) atoms. In the second S site, S(2) is bonded in a distorted pentagonal planar geometry to two equivalent Er(1), one Cu(1), and two equivalent Cu(2) atoms. In the third S site, S(3) is bonded to three equivalent Er(1), two equivalent Cu(2), and one Tl(1) atom to form a mixture of distorted edge and corner-sharing SEr3TlCu2 square pyramids. is represented by the CIF file [CIF]
data_Er2TlCu3S5
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   7.180
_cell_length_b   7.180
_cell_length_c   16.311
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   148.404
_symmetry_Int_Tables_number   1
_cell_volume   440.548
_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
  Er  Er0  1  0.808  0.192  0.094  1.0
  Er  Er1  1  0.192  0.808  0.906  1.0
  Er  Er2  1  0.808  0.192  0.406  1.0
  Er  Er3  1  0.192  0.808  0.594  1.0
  Tl  Tl4  1  0.071  0.929  0.250  1.0
  Tl  Tl5  1  0.929  0.071  0.750  1.0
  Cu  Cu6  1  0.353  0.647  0.250  1.0
  Cu  Cu7  1  0.647  0.353  0.750  1.0
  Cu  Cu8  1  0.583  0.417  0.459  1.0
  Cu  Cu9  1  0.417  0.583  0.541  1.0
  Cu  Cu10  1  0.583  0.417  0.041  1.0
  Cu  Cu11  1  0.417  0.583  0.959  1.0
  S  S12  1  0.759  0.241  0.250  1.0
  S  S13  1  0.241  0.759  0.750  1.0
  S  S14  1  0.561  0.439  0.885  1.0
  S  S15  1  0.439  0.561  0.115  1.0
  S  S16  1  0.561  0.439  0.615  1.0
  S  S17  1  0.439  0.561  0.385  1.0
  S  S18  1  0.832  0.168  0.930  1.0
  S  S19  1  0.168  0.832  0.070  1.0
  S  S20  1  0.832  0.168  0.570  1.0
  S  S21  1  0.168  0.832  0.430  1.0
[/CIF]
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The crystal structure described by Er2Cu3TlS5 crystallizes in the orthorhombic Cmcm space group. Er(1) is bonded to one S(1), two equivalent S(2), and three equivalent S(3) atoms to form ErS6 octahedra that share  a cornercorner with one Er(1)S6 octahedra, corners with four equivalent Cu(2)S4 tetrahedra, edges with four equivalent Er(1)S6 octahedra, edges with two equivalent Cu(1)S4 tetrahedra, and edges with three equivalent Cu(2)S4 tetrahedra. The corner-sharing octahedral tilt angles are 30°. There are two inequivalent Cu sites. In the first Cu site, Cu(1) is bonded to two equivalent S(1) and two equivalent S(2) atoms to form CuS4 tetrahedra that share corners with two equivalent Cu(1)S4 tetrahedra, corners with four equivalent Cu(2)S4 tetrahedra, and edges with four equivalent Er(1)S6 octahedra. In the second Cu site, Cu(2) is bonded to two equivalent S(2) and two equivalent S(3) atoms to form distorted CuS4 tetrahedra that share corners with four equivalent Er(1)S6 octahedra, corners with two equivalent Cu(1)S4 tetrahedra, corners with two equivalent Cu(2)S4 tetrahedra, edges with three equivalent Er(1)S6 octahedra, and  an edgeedge with one Cu(2)S4 tetrahedra. The corner-sharing octahedral tilt angles range from 14-60°. Tl(1) is bonded in a 4-coordinate geometry to two equivalent S(1) and two equivalent S(3) atoms. There are three inequivalent S sites. In the first S site, S(1) is bonded in a 4-coordinate geometry to two equivalent Er(1), two equivalent Cu(1), and two equivalent Tl(1) atoms. In the second S site, S(2) is bonded in a distorted pentagonal planar geometry to two equivalent Er(1), one Cu(1), and two equivalent Cu(2) atoms. In the third S site, S(3) is bonded to three equivalent Er(1), two equivalent Cu(2), and one Tl(1) atom to form a mixture of distorted edge and corner-sharing SEr3TlCu2 square pyramids. is represented by the CIF file [CIF]
data_Er2TlCu3S5
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   7.180
_cell_length_b   7.180
_cell_length_c   16.311
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   148.404
_symmetry_Int_Tables_number   1
_cell_volume   440.548
_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
  Er  Er0  1  0.808  0.192  0.094  1.0
  Er  Er1  1  0.192  0.808  0.906  1.0
  Er  Er2  1  0.808  0.192  0.406  1.0
  Er  Er3  1  0.192  0.808  0.594  1.0
  Tl  Tl4  1  0.071  0.929  0.250  1.0
  Tl  Tl5  1  0.929  0.071  0.750  1.0
  Cu  Cu6  1  0.353  0.647  0.250  1.0
  Cu  Cu7  1  0.647  0.353  0.750  1.0
  Cu  Cu8  1  0.583  0.417  0.459  1.0
  Cu  Cu9  1  0.417  0.583  0.541  1.0
  Cu  Cu10  1  0.583  0.417  0.041  1.0
  Cu  Cu11  1  0.417  0.583  0.959  1.0
  S  S12  1  0.759  0.241  0.250  1.0
  S  S13  1  0.241  0.759  0.750  1.0
  S  S14  1  0.561  0.439  0.885  1.0
  S  S15  1  0.439  0.561  0.115  1.0
  S  S16  1  0.561  0.439  0.615  1.0
  S  S17  1  0.439  0.561  0.385  1.0
  S  S18  1  0.832  0.168  0.930  1.0
  S  S19  1  0.168  0.832  0.070  1.0
  S  S20  1  0.832  0.168  0.570  1.0
  S  S21  1  0.168  0.832  0.430  1.0
[/CIF]
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