The compound described by Cu9Se5 crystallizes in the triclinic P-1 space group. There are nine inequivalent Cu sites. In the first Cu site, Cu(1) is bonded to one Se(1), one Se(2), and two equivalent Se(5) atoms to form a mixture of corner and edge-sharing CuSe4 tetrahedra. In the second Cu site, Cu(2) is bonded to one Se(1), one Se(2), and two equivalent Se(3) atoms to form a mixture of corner and edge-sharing CuSe4 tetrahedra. In the third Cu site, Cu(3) is bonded to one Se(1), one Se(4), and two equivalent Se(2) atoms to form a mixture of corner and edge-sharing CuSe4 tetrahedra. In the fourth Cu site, Cu(4) is bonded to one Se(2), one Se(5), and two equivalent Se(4) atoms to form a mixture of corner and edge-sharing CuSe4 tetrahedra. In the fifth Cu site, Cu(5) is bonded to one Se(2), one Se(3), and two equivalent Se(5) atoms to form a mixture of corner and edge-sharing CuSe4 tetrahedra. In the sixth Cu site, Cu(6) is bonded to one Se(1), one Se(3), one Se(4), and one Se(5) atom to form a mixture of corner and edge-sharing CuSe4 tetrahedra. In the seventh Cu site, Cu(7) is bonded to one Se(1), one Se(5), and two equivalent Se(3) atoms to form a mixture of corner and edge-sharing CuSe4 tetrahedra. In the eighth Cu site, Cu(8) is bonded to one Se(2), one Se(4), and two equivalent Se(1) atoms to form a mixture of corner and edge-sharing CuSe4 tetrahedra. In the ninth Cu site, Cu(9) is bonded to one Se(1), one Se(3), and two equivalent Se(4) atoms to form a mixture of corner and edge-sharing CuSe4 tetrahedra. There are five inequivalent Se sites. In the first Se site, Se(1) is bonded in a body-centered cubic geometry to one Cu(1), one Cu(2), one Cu(3), one Cu(6), one Cu(7), one Cu(9), and two equivalent Cu(8) atoms. In the second Se site, Se(2) is bonded in a 7-coordinate geometry to one Cu(1), one Cu(2), one Cu(4), one Cu(5), one Cu(8), and two equivalent Cu(3) atoms. In the third Se site, Se(3) is bonded in a 7-coordinate geometry to one Cu(5), one Cu(6), one Cu(9), two equivalent Cu(2), and two equivalent Cu(7) atoms. In the fourth Se site, Se(4) is bonded in a 7-coordinate geometry to one Cu(3), one Cu(6), one Cu(8), two equivalent Cu(4), and two equivalent Cu(9) atoms. In the fifth Se site, Se(5) is bonded in a 7-coordinate geometry to one Cu(4), one Cu(6), one Cu(7), two equivalent Cu(1), and two equivalent Cu(5) atoms. is represented by the CIF file [CIF]
data_Cu9Se5
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   7.021
_cell_length_b   8.114
_cell_length_c   9.087
_cell_angle_alpha   77.122
_cell_angle_beta   75.025
_cell_angle_gamma   73.288
_symmetry_Int_Tables_number   1
_cell_volume   472.747
_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
  Cu  Cu0  1  0.049  0.451  0.149  1.0
  Cu  Cu1  1  0.049  0.950  0.149  1.0
  Cu  Cu2  1  0.951  0.050  0.851  1.0
  Cu  Cu3  1  0.150  0.350  0.451  1.0
  Cu  Cu4  1  0.951  0.549  0.851  1.0
  Cu  Cu5  1  0.446  0.552  0.349  1.0
  Cu  Cu6  1  0.349  0.651  0.046  1.0
  Cu  Cu7  1  0.254  0.750  0.747  1.0
  Cu  Cu8  1  0.649  0.850  0.951  1.0
  Cu  Cu9  1  0.151  0.849  0.450  1.0
  Cu  Cu10  1  0.549  0.950  0.650  1.0
  Cu  Cu11  1  0.451  0.050  0.350  1.0
  Cu  Cu12  1  0.351  0.150  0.049  1.0
  Cu  Cu13  1  0.849  0.151  0.550  1.0
  Cu  Cu14  1  0.651  0.349  0.954  1.0
  Cu  Cu15  1  0.554  0.448  0.651  1.0
  Cu  Cu16  1  0.850  0.650  0.549  1.0
  Cu  Cu17  1  0.746  0.250  0.253  1.0
  Se  Se18  1  0.899  0.850  0.700  1.0
  Se  Se19  1  0.905  0.349  0.700  1.0
  Se  Se20  1  0.095  0.651  0.300  1.0
  Se  Se21  1  0.299  0.954  0.899  1.0
  Se  Se22  1  0.101  0.150  0.300  1.0
  Se  Se23  1  0.497  0.250  0.503  1.0
  Se  Se24  1  0.298  0.447  0.898  1.0
  Se  Se25  1  0.702  0.553  0.102  1.0
  Se  Se26  1  0.503  0.750  0.497  1.0
  Se  Se27  1  0.701  0.046  0.101  1.0
[/CIF]
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The compound described by Cu9Se5 crystallizes in the triclinic P-1 space group. There are nine inequivalent Cu sites. In the first Cu site, Cu(1) is bonded to one Se(1), one Se(2), and two equivalent Se(5) atoms to form a mixture of corner and edge-sharing CuSe4 tetrahedra. In the second Cu site, Cu(2) is bonded to one Se(1), one Se(2), and two equivalent Se(3) atoms to form a mixture of corner and edge-sharing CuSe4 tetrahedra. In the third Cu site, Cu(3) is bonded to one Se(1), one Se(4), and two equivalent Se(2) atoms to form a mixture of corner and edge-sharing CuSe4 tetrahedra. In the fourth Cu site, Cu(4) is bonded to one Se(2), one Se(5), and two equivalent Se(4) atoms to form a mixture of corner and edge-sharing CuSe4 tetrahedra. In the fifth Cu site, Cu(5) is bonded to one Se(2), one Se(3), and two equivalent Se(5) atoms to form a mixture of corner and edge-sharing CuSe4 tetrahedra. In the sixth Cu site, Cu(6) is bonded to one Se(1), one Se(3), one Se(4), and one Se(5) atom to form a mixture of corner and edge-sharing CuSe4 tetrahedra. In the seventh Cu site, Cu(7) is bonded to one Se(1), one Se(5), and two equivalent Se(3) atoms to form a mixture of corner and edge-sharing CuSe4 tetrahedra. In the eighth Cu site, Cu(8) is bonded to one Se(2), one Se(4), and two equivalent Se(1) atoms to form a mixture of corner and edge-sharing CuSe4 tetrahedra. In the ninth Cu site, Cu(9) is bonded to one Se(1), one Se(3), and two equivalent Se(4) atoms to form a mixture of corner and edge-sharing CuSe4 tetrahedra. There are five inequivalent Se sites. In the first Se site, Se(1) is bonded in a body-centered cubic geometry to one Cu(1), one Cu(2), one Cu(3), one Cu(6), one Cu(7), one Cu(9), and two equivalent Cu(8) atoms. In the second Se site, Se(2) is bonded in a 7-coordinate geometry to one Cu(1), one Cu(2), one Cu(4), one Cu(5), one Cu(8), and two equivalent Cu(3) atoms. In the third Se site, Se(3) is bonded in a 7-coordinate geometry to one Cu(5), one Cu(6), one Cu(9), two equivalent Cu(2), and two equivalent Cu(7) atoms. In the fourth Se site, Se(4) is bonded in a 7-coordinate geometry to one Cu(3), one Cu(6), one Cu(8), two equivalent Cu(4), and two equivalent Cu(9) atoms. In the fifth Se site, Se(5) is bonded in a 7-coordinate geometry to one Cu(4), one Cu(6), one Cu(7), two equivalent Cu(1), and two equivalent Cu(5) atoms. is represented by the CIF file [CIF]
data_Cu9Se5
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   7.021
_cell_length_b   8.114
_cell_length_c   9.087
_cell_angle_alpha   77.122
_cell_angle_beta   75.025
_cell_angle_gamma   73.288
_symmetry_Int_Tables_number   1
_cell_volume   472.747
_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
  Cu  Cu0  1  0.049  0.451  0.149  1.0
  Cu  Cu1  1  0.049  0.950  0.149  1.0
  Cu  Cu2  1  0.951  0.050  0.851  1.0
  Cu  Cu3  1  0.150  0.350  0.451  1.0
  Cu  Cu4  1  0.951  0.549  0.851  1.0
  Cu  Cu5  1  0.446  0.552  0.349  1.0
  Cu  Cu6  1  0.349  0.651  0.046  1.0
  Cu  Cu7  1  0.254  0.750  0.747  1.0
  Cu  Cu8  1  0.649  0.850  0.951  1.0
  Cu  Cu9  1  0.151  0.849  0.450  1.0
  Cu  Cu10  1  0.549  0.950  0.650  1.0
  Cu  Cu11  1  0.451  0.050  0.350  1.0
  Cu  Cu12  1  0.351  0.150  0.049  1.0
  Cu  Cu13  1  0.849  0.151  0.550  1.0
  Cu  Cu14  1  0.651  0.349  0.954  1.0
  Cu  Cu15  1  0.554  0.448  0.651  1.0
  Cu  Cu16  1  0.850  0.650  0.549  1.0
  Cu  Cu17  1  0.746  0.250  0.253  1.0
  Se  Se18  1  0.899  0.850  0.700  1.0
  Se  Se19  1  0.905  0.349  0.700  1.0
  Se  Se20  1  0.095  0.651  0.300  1.0
  Se  Se21  1  0.299  0.954  0.899  1.0
  Se  Se22  1  0.101  0.150  0.300  1.0
  Se  Se23  1  0.497  0.250  0.503  1.0
  Se  Se24  1  0.298  0.447  0.898  1.0
  Se  Se25  1  0.702  0.553  0.102  1.0
  Se  Se26  1  0.503  0.750  0.497  1.0
  Se  Se27  1  0.701  0.046  0.101  1.0
[/CIF]
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