The material structure described by Cu9Se8 is Aluminum carbonitride-derived structured and crystallizes in the triclinic P1 space group. There are nine inequivalent Cu sites. In the first Cu site, Cu(1) is bonded to one Se(2) and three equivalent Se(1) atoms to form distorted corner-sharing CuSe4 tetrahedra. In the second Cu site, Cu(2) is bonded in a 4-coordinate geometry to one Se(3) and three equivalent Se(2) atoms. In the third Cu site, Cu(3) is bonded in a 4-coordinate geometry to one Se(2) and three equivalent Se(3) atoms. In the fourth Cu site, Cu(4) is bonded to one Se(3) and three equivalent Se(5) atoms to form corner-sharing CuSe4 tetrahedra. In the fifth Cu site, Cu(5) is bonded to one Se(5) and three equivalent Se(4) atoms to form corner-sharing CuSe4 tetrahedra. In the sixth Cu site, Cu(6) is bonded to one Se(4) and three equivalent Se(6) atoms to form corner-sharing CuSe4 tetrahedra. In the seventh Cu site, Cu(7) is bonded to one Se(6) and three equivalent Se(7) atoms to form corner-sharing CuSe4 tetrahedra. In the eighth Cu site, Cu(8) is bonded to one Se(7) and three equivalent Se(8) atoms to form corner-sharing CuSe4 tetrahedra. In the ninth Cu site, Cu(9) is bonded in a 4-coordinate geometry to one Se(8) and three equivalent Se(1) atoms. There are eight inequivalent Se sites. In the first Se site, Se(1) is bonded to three equivalent Cu(1) and three equivalent Cu(9) atoms to form distorted SeCu6 octahedra that share corners with three equivalent Se(8)Cu4 tetrahedra and edges with six equivalent Se(1)Cu6 octahedra. In the second Se site, Se(2) is bonded in a 5-coordinate geometry to one Cu(1), one Cu(3), and three equivalent Cu(2) atoms. In the third Se site, Se(3) is bonded in a 5-coordinate geometry to one Cu(2), one Cu(4), and three equivalent Cu(3) atoms. In the fourth Se site, Se(4) is bonded to one Cu(6) and three equivalent Cu(5) atoms to form corner-sharing SeCu4 tetrahedra. In the fifth Se site, Se(5) is bonded to one Cu(5) and three equivalent Cu(4) atoms to form corner-sharing SeCu4 tetrahedra. In the sixth Se site, Se(6) is bonded to one Cu(7) and three equivalent Cu(6) atoms to form corner-sharing SeCu4 tetrahedra. In the seventh Se site, Se(7) is bonded to one Cu(8) and three equivalent Cu(7) atoms to form corner-sharing SeCu4 tetrahedra. In the eighth Se site, Se(8) is bonded to one Cu(9) and three equivalent Cu(8) atoms to form SeCu4 tetrahedra that share corners with three equivalent Se(1)Cu6 octahedra, corners with three equivalent Se(7)Cu4 tetrahedra, and corners with six equivalent Se(8)Cu4 tetrahedra. The corner-sharing octahedral tilt angles range from 55-78°. is represented by the CIF card [CIF]
data_Cu9Se8
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   3.870
_cell_length_b   3.907
_cell_length_c   26.269
_cell_angle_alpha   94.148
_cell_angle_beta   89.784
_cell_angle_gamma   119.658
_symmetry_Int_Tables_number   1
_cell_volume   343.989
_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
  Cu  Cu0  1  0.272  0.609  0.032  1.0
  Cu  Cu1  1  0.725  0.128  0.153  1.0
  Cu  Cu2  1  0.370  0.412  0.219  1.0
  Cu  Cu3  1  0.751  0.909  0.343  1.0
  Cu  Cu4  1  0.125  0.413  0.465  1.0
  Cu  Cu5  1  0.500  0.914  0.590  1.0
  Cu  Cu6  1  0.874  0.414  0.715  1.0
  Cu  Cu7  1  0.248  0.914  0.838  1.0
  Cu  Cu8  1  0.597  0.404  0.958  1.0
  Se  Se9  1  0.938  0.006  0.996  1.0
  Se  Se10  1  0.383  0.511  0.122  1.0
  Se  Se11  1  0.713  0.028  0.250  1.0
  Se  Se12  1  0.466  0.031  0.498  1.0
  Se  Se13  1  0.092  0.530  0.374  1.0
  Se  Se14  1  0.841  0.532  0.623  1.0
  Se  Se15  1  0.215  0.033  0.746  1.0
  Se  Se16  1  0.588  0.534  0.868  1.0
[/CIF]
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The material structure described by Cu9Se8 is Aluminum carbonitride-derived structured and crystallizes in the triclinic P1 space group. There are nine inequivalent Cu sites. In the first Cu site, Cu(1) is bonded to one Se(2) and three equivalent Se(1) atoms to form distorted corner-sharing CuSe4 tetrahedra. In the second Cu site, Cu(2) is bonded in a 4-coordinate geometry to one Se(3) and three equivalent Se(2) atoms. In the third Cu site, Cu(3) is bonded in a 4-coordinate geometry to one Se(2) and three equivalent Se(3) atoms. In the fourth Cu site, Cu(4) is bonded to one Se(3) and three equivalent Se(5) atoms to form corner-sharing CuSe4 tetrahedra. In the fifth Cu site, Cu(5) is bonded to one Se(5) and three equivalent Se(4) atoms to form corner-sharing CuSe4 tetrahedra. In the sixth Cu site, Cu(6) is bonded to one Se(4) and three equivalent Se(6) atoms to form corner-sharing CuSe4 tetrahedra. In the seventh Cu site, Cu(7) is bonded to one Se(6) and three equivalent Se(7) atoms to form corner-sharing CuSe4 tetrahedra. In the eighth Cu site, Cu(8) is bonded to one Se(7) and three equivalent Se(8) atoms to form corner-sharing CuSe4 tetrahedra. In the ninth Cu site, Cu(9) is bonded in a 4-coordinate geometry to one Se(8) and three equivalent Se(1) atoms. There are eight inequivalent Se sites. In the first Se site, Se(1) is bonded to three equivalent Cu(1) and three equivalent Cu(9) atoms to form distorted SeCu6 octahedra that share corners with three equivalent Se(8)Cu4 tetrahedra and edges with six equivalent Se(1)Cu6 octahedra. In the second Se site, Se(2) is bonded in a 5-coordinate geometry to one Cu(1), one Cu(3), and three equivalent Cu(2) atoms. In the third Se site, Se(3) is bonded in a 5-coordinate geometry to one Cu(2), one Cu(4), and three equivalent Cu(3) atoms. In the fourth Se site, Se(4) is bonded to one Cu(6) and three equivalent Cu(5) atoms to form corner-sharing SeCu4 tetrahedra. In the fifth Se site, Se(5) is bonded to one Cu(5) and three equivalent Cu(4) atoms to form corner-sharing SeCu4 tetrahedra. In the sixth Se site, Se(6) is bonded to one Cu(7) and three equivalent Cu(6) atoms to form corner-sharing SeCu4 tetrahedra. In the seventh Se site, Se(7) is bonded to one Cu(8) and three equivalent Cu(7) atoms to form corner-sharing SeCu4 tetrahedra. In the eighth Se site, Se(8) is bonded to one Cu(9) and three equivalent Cu(8) atoms to form SeCu4 tetrahedra that share corners with three equivalent Se(1)Cu6 octahedra, corners with three equivalent Se(7)Cu4 tetrahedra, and corners with six equivalent Se(8)Cu4 tetrahedra. The corner-sharing octahedral tilt angles range from 55-78°. is represented by the CIF card [CIF]
data_Cu9Se8
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   3.870
_cell_length_b   3.907
_cell_length_c   26.269
_cell_angle_alpha   94.148
_cell_angle_beta   89.784
_cell_angle_gamma   119.658
_symmetry_Int_Tables_number   1
_cell_volume   343.989
_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
  Cu  Cu0  1  0.272  0.609  0.032  1.0
  Cu  Cu1  1  0.725  0.128  0.153  1.0
  Cu  Cu2  1  0.370  0.412  0.219  1.0
  Cu  Cu3  1  0.751  0.909  0.343  1.0
  Cu  Cu4  1  0.125  0.413  0.465  1.0
  Cu  Cu5  1  0.500  0.914  0.590  1.0
  Cu  Cu6  1  0.874  0.414  0.715  1.0
  Cu  Cu7  1  0.248  0.914  0.838  1.0
  Cu  Cu8  1  0.597  0.404  0.958  1.0
  Se  Se9  1  0.938  0.006  0.996  1.0
  Se  Se10  1  0.383  0.511  0.122  1.0
  Se  Se11  1  0.713  0.028  0.250  1.0
  Se  Se12  1  0.466  0.031  0.498  1.0
  Se  Se13  1  0.092  0.530  0.374  1.0
  Se  Se14  1  0.841  0.532  0.623  1.0
  Se  Se15  1  0.215  0.033  0.746  1.0
  Se  Se16  1  0.588  0.534  0.868  1.0
[/CIF]
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