The crystal structure described by HoCuPbSe3 crystallizes in the orthorhombic Pnma space group. Ho(1) is bonded to two equivalent Se(1), two equivalent Se(2), and two equivalent Se(3) atoms to form HoSe6 octahedra that share corners with two equivalent Ho(1)Se6 octahedra, edges with two equivalent Ho(1)Se6 octahedra, and edges with four equivalent Cu(1)Se4 tetrahedra. The corner-sharing octahedral tilt angles are 45°. 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 Ho(1)Se6 octahedra. Pb(1) is bonded in a 7-coordinate geometry to two equivalent Se(2), two equivalent Se(3), and three equivalent Se(1) atoms. There are three inequivalent Se sites. In the first Se site, Se(1) is bonded in a 3-coordinate geometry to two equivalent Ho(1), one Cu(1), and three equivalent Pb(1) atoms. In the second Se site, Se(2) is bonded in a 5-coordinate geometry to two equivalent Ho(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 Ho(1), two equivalent Cu(1), and two equivalent Pb(1) atoms. is represented by the Crystallographic Information File (CIF) [CIF]
data_HoCuPbSe3
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   4.058
_cell_length_b   10.606
_cell_length_c   13.667
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   588.206
_cell_formula_units_Z   4
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
  Ho  Ho0  1  0.750  0.978  0.244  1.0
  Ho  Ho1  1  0.250  0.022  0.756  1.0
  Ho  Ho2  1  0.750  0.478  0.256  1.0
  Ho  Ho3  1  0.250  0.522  0.744  1.0
  Cu  Cu4  1  0.250  0.735  0.222  1.0
  Cu  Cu5  1  0.750  0.265  0.778  1.0
  Cu  Cu6  1  0.250  0.235  0.278  1.0
  Cu  Cu7  1  0.750  0.765  0.722  1.0
  Pb  Pb8  1  0.750  0.723  0.006  1.0
  Pb  Pb9  1  0.250  0.277  0.994  1.0
  Pb  Pb10  1  0.750  0.223  0.494  1.0
  Pb  Pb11  1  0.250  0.777  0.506  1.0
  Se  Se12  1  0.750  0.455  0.885  1.0
  Se  Se13  1  0.250  0.545  0.115  1.0
  Se  Se14  1  0.750  0.955  0.615  1.0
  Se  Se15  1  0.250  0.045  0.385  1.0
  Se  Se16  1  0.250  0.412  0.392  1.0
  Se  Se17  1  0.750  0.588  0.608  1.0
  Se  Se18  1  0.250  0.912  0.108  1.0
  Se  Se19  1  0.750  0.088  0.892  1.0
  Se  Se20  1  0.750  0.231  0.170  1.0
  Se  Se21  1  0.250  0.769  0.830  1.0
  Se  Se22  1  0.750  0.731  0.330  1.0
  Se  Se23  1  0.250  0.269  0.670  1.0
[/CIF]
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The crystal structure described by HoCuPbSe3 crystallizes in the orthorhombic Pnma space group. Ho(1) is bonded to two equivalent Se(1), two equivalent Se(2), and two equivalent Se(3) atoms to form HoSe6 octahedra that share corners with two equivalent Ho(1)Se6 octahedra, edges with two equivalent Ho(1)Se6 octahedra, and edges with four equivalent Cu(1)Se4 tetrahedra. The corner-sharing octahedral tilt angles are 45°. 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 Ho(1)Se6 octahedra. Pb(1) is bonded in a 7-coordinate geometry to two equivalent Se(2), two equivalent Se(3), and three equivalent Se(1) atoms. There are three inequivalent Se sites. In the first Se site, Se(1) is bonded in a 3-coordinate geometry to two equivalent Ho(1), one Cu(1), and three equivalent Pb(1) atoms. In the second Se site, Se(2) is bonded in a 5-coordinate geometry to two equivalent Ho(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 Ho(1), two equivalent Cu(1), and two equivalent Pb(1) atoms. is represented by the Crystallographic Information File (CIF) [CIF]
data_HoCuPbSe3
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   4.058
_cell_length_b   10.606
_cell_length_c   13.667
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   588.206
_cell_formula_units_Z   4
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
  Ho  Ho0  1  0.750  0.978  0.244  1.0
  Ho  Ho1  1  0.250  0.022  0.756  1.0
  Ho  Ho2  1  0.750  0.478  0.256  1.0
  Ho  Ho3  1  0.250  0.522  0.744  1.0
  Cu  Cu4  1  0.250  0.735  0.222  1.0
  Cu  Cu5  1  0.750  0.265  0.778  1.0
  Cu  Cu6  1  0.250  0.235  0.278  1.0
  Cu  Cu7  1  0.750  0.765  0.722  1.0
  Pb  Pb8  1  0.750  0.723  0.006  1.0
  Pb  Pb9  1  0.250  0.277  0.994  1.0
  Pb  Pb10  1  0.750  0.223  0.494  1.0
  Pb  Pb11  1  0.250  0.777  0.506  1.0
  Se  Se12  1  0.750  0.455  0.885  1.0
  Se  Se13  1  0.250  0.545  0.115  1.0
  Se  Se14  1  0.750  0.955  0.615  1.0
  Se  Se15  1  0.250  0.045  0.385  1.0
  Se  Se16  1  0.250  0.412  0.392  1.0
  Se  Se17  1  0.750  0.588  0.608  1.0
  Se  Se18  1  0.250  0.912  0.108  1.0
  Se  Se19  1  0.750  0.088  0.892  1.0
  Se  Se20  1  0.750  0.231  0.170  1.0
  Se  Se21  1  0.250  0.769  0.830  1.0
  Se  Se22  1  0.750  0.731  0.330  1.0
  Se  Se23  1  0.250  0.269  0.670  1.0
[/CIF]
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