The structure described by CuTl2Se2 crystallizes in the tetragonal I4/mmm space group. Cu(1) is bonded in a linear geometry to two equivalent Se(1) atoms. Tl(1) is bonded in a rectangular see-saw-like geometry to four equivalent Se(1) atoms. Se(1) is bonded to one Cu(1) and four equivalent Tl(1) atoms to form a mixture of corner and edge-sharing SeTl4Cu square pyramids. is represented by the CIF card [CIF]
data_Tl2CuSe2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   6.267
_cell_length_b   6.267
_cell_length_c   6.237
_cell_angle_alpha   120.157
_cell_angle_beta   120.157
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   172.377
_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  0.250  0.750  0.500  1.0
  Tl  Tl1  1  0.750  0.250  0.500  1.0
  Cu  Cu2  1  0.000  0.000  0.000  1.0
  Se  Se3  1  0.255  0.255  0.510  1.0
  Se  Se4  1  0.745  0.745  0.490  1.0
[/CIF]
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The structure described by CuTl2Se2 crystallizes in the tetragonal I4/mmm space group. Cu(1) is bonded in a linear geometry to two equivalent Se(1) atoms. Tl(1) is bonded in a rectangular see-saw-like geometry to four equivalent Se(1) atoms. Se(1) is bonded to one Cu(1) and four equivalent Tl(1) atoms to form a mixture of corner and edge-sharing SeTl4Cu square pyramids. is represented by the CIF card [CIF]
data_Tl2CuSe2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   6.267
_cell_length_b   6.267
_cell_length_c   6.237
_cell_angle_alpha   120.157
_cell_angle_beta   120.157
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   172.377
_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  0.250  0.750  0.500  1.0
  Tl  Tl1  1  0.750  0.250  0.500  1.0
  Cu  Cu2  1  0.000  0.000  0.000  1.0
  Se  Se3  1  0.255  0.255  0.510  1.0
  Se  Se4  1  0.745  0.745  0.490  1.0
[/CIF]
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