The crystal structure described by TmCuPbSe3 crystallizes in the orthorhombic Cmc2_1 space group. Tm(1) is bonded to two equivalent Se(1), two equivalent Se(2), and two equivalent Se(3) atoms to form TmSe6 octahedra that share corners with two equivalent Tm(1)Se6 octahedra, edges with two equivalent Tm(1)Se6 octahedra, and edges with four equivalent Cu(1)Se4 tetrahedra. The corner-sharing octahedral tilt angles are 43°. Cu(1) is bonded to one Se(1), one Se(2), and two equivalent Se(3) atoms to form CuSe4 tetrahedra that share corners with two equivalent Cu(1)Se4 tetrahedra and edges with four equivalent Tm(1)Se6 octahedra. Pb(1) is bonded in a 6-coordinate geometry to two equivalent Se(1), two equivalent Se(2), and two equivalent Se(3) atoms. There are three inequivalent Se sites. In the first Se site, Se(1) is bonded in a 5-coordinate geometry to two equivalent Tm(1), one Cu(1), and two equivalent Pb(1) atoms. In the second Se site, Se(2) is bonded in a 3-coordinate geometry to two equivalent Tm(1), one Cu(1), and two equivalent Pb(1) atoms. In the third Se site, Se(3) is bonded in a 6-coordinate geometry to two equivalent Tm(1), two equivalent Cu(1), and two equivalent Pb(1) atoms. is represented by the CIF card [CIF]
data_TmCuPbSe3
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   7.092
_cell_length_b   7.092
_cell_length_c   10.548
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   146.844
_symmetry_Int_Tables_number   1
_cell_volume   290.160
_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
  Tm  Tm0  1  0.499  0.501  0.497  1.0
  Tm  Tm1  1  0.501  0.499  0.997  1.0
  Cu  Cu2  1  0.034  0.966  0.245  1.0
  Cu  Cu3  1  0.966  0.034  0.745  1.0
  Pb  Pb4  1  0.257  0.743  0.757  1.0
  Pb  Pb5  1  0.743  0.257  0.257  1.0
  Se  Se6  1  0.141  0.859  0.432  1.0
  Se  Se7  1  0.142  0.858  0.057  1.0
  Se  Se8  1  0.859  0.141  0.932  1.0
  Se  Se9  1  0.858  0.142  0.557  1.0
  Se  Se10  1  0.424  0.576  0.247  1.0
  Se  Se11  1  0.576  0.424  0.747  1.0
[/CIF]
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The crystal structure described by TmCuPbSe3 crystallizes in the orthorhombic Cmc2_1 space group. Tm(1) is bonded to two equivalent Se(1), two equivalent Se(2), and two equivalent Se(3) atoms to form TmSe6 octahedra that share corners with two equivalent Tm(1)Se6 octahedra, edges with two equivalent Tm(1)Se6 octahedra, and edges with four equivalent Cu(1)Se4 tetrahedra. The corner-sharing octahedral tilt angles are 43°. Cu(1) is bonded to one Se(1), one Se(2), and two equivalent Se(3) atoms to form CuSe4 tetrahedra that share corners with two equivalent Cu(1)Se4 tetrahedra and edges with four equivalent Tm(1)Se6 octahedra. Pb(1) is bonded in a 6-coordinate geometry to two equivalent Se(1), two equivalent Se(2), and two equivalent Se(3) atoms. There are three inequivalent Se sites. In the first Se site, Se(1) is bonded in a 5-coordinate geometry to two equivalent Tm(1), one Cu(1), and two equivalent Pb(1) atoms. In the second Se site, Se(2) is bonded in a 3-coordinate geometry to two equivalent Tm(1), one Cu(1), and two equivalent Pb(1) atoms. In the third Se site, Se(3) is bonded in a 6-coordinate geometry to two equivalent Tm(1), two equivalent Cu(1), and two equivalent Pb(1) atoms. is represented by the CIF card [CIF]
data_TmCuPbSe3
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   7.092
_cell_length_b   7.092
_cell_length_c   10.548
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   146.844
_symmetry_Int_Tables_number   1
_cell_volume   290.160
_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
  Tm  Tm0  1  0.499  0.501  0.497  1.0
  Tm  Tm1  1  0.501  0.499  0.997  1.0
  Cu  Cu2  1  0.034  0.966  0.245  1.0
  Cu  Cu3  1  0.966  0.034  0.745  1.0
  Pb  Pb4  1  0.257  0.743  0.757  1.0
  Pb  Pb5  1  0.743  0.257  0.257  1.0
  Se  Se6  1  0.141  0.859  0.432  1.0
  Se  Se7  1  0.142  0.858  0.057  1.0
  Se  Se8  1  0.859  0.141  0.932  1.0
  Se  Se9  1  0.858  0.142  0.557  1.0
  Se  Se10  1  0.424  0.576  0.247  1.0
  Se  Se11  1  0.576  0.424  0.747  1.0
[/CIF]
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