The structure described by Y(CuSe)3 crystallizes in the trigonal R-3 space group. Y(1) is bonded to six equivalent Se(1) atoms to form YSe6 octahedra that share corners with twelve equivalent Cu(1)Se4 tetrahedra, edges with three equivalent Y(1)Se6 octahedra, and edges with six equivalent Cu(1)Se4 tetrahedra. Cu(1) is bonded to four equivalent Se(1) atoms to form CuSe4 tetrahedra that share corners with four equivalent Y(1)Se6 octahedra, corners with six equivalent Cu(1)Se4 tetrahedra, edges with two equivalent Y(1)Se6 octahedra, and edges with three equivalent Cu(1)Se4 tetrahedra. The corner-sharing octahedral tilt angles range from 15-57°. Se(1) is bonded to two equivalent Y(1) and four equivalent Cu(1) atoms to form a mixture of distorted corner and edge-sharing SeY2Cu4 octahedra. The corner-sharing octahedral tilt angles range from 1-92°. is represented by the CIF card [CIF]
data_Y(CuSe)3
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   7.777
_cell_length_b   7.777
_cell_length_c   7.777
_cell_angle_alpha   53.765
_cell_angle_beta   53.765
_cell_angle_gamma   53.765
_symmetry_Int_Tables_number   1
_cell_volume   284.173
_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
  Y  Y0  1  0.834  0.834  0.834  1.0
  Y  Y1  1  0.166  0.166  0.166  1.0
  Cu  Cu2  1  0.279  0.969  0.626  1.0
  Cu  Cu3  1  0.626  0.279  0.969  1.0
  Cu  Cu4  1  0.969  0.626  0.279  1.0
  Cu  Cu5  1  0.031  0.374  0.721  1.0
  Cu  Cu6  1  0.374  0.721  0.031  1.0
  Cu  Cu7  1  0.721  0.031  0.374  1.0
  Se  Se8  1  0.089  0.744  0.419  1.0
  Se  Se9  1  0.744  0.419  0.089  1.0
  Se  Se10  1  0.419  0.089  0.744  1.0
  Se  Se11  1  0.581  0.911  0.256  1.0
  Se  Se12  1  0.256  0.581  0.911  1.0
  Se  Se13  1  0.911  0.256  0.581  1.0
[/CIF]
.
The structure described by Y(CuSe)3 crystallizes in the trigonal R-3 space group. Y(1) is bonded to six equivalent Se(1) atoms to form YSe6 octahedra that share corners with twelve equivalent Cu(1)Se4 tetrahedra, edges with three equivalent Y(1)Se6 octahedra, and edges with six equivalent Cu(1)Se4 tetrahedra. Cu(1) is bonded to four equivalent Se(1) atoms to form CuSe4 tetrahedra that share corners with four equivalent Y(1)Se6 octahedra, corners with six equivalent Cu(1)Se4 tetrahedra, edges with two equivalent Y(1)Se6 octahedra, and edges with three equivalent Cu(1)Se4 tetrahedra. The corner-sharing octahedral tilt angles range from 15-57°. Se(1) is bonded to two equivalent Y(1) and four equivalent Cu(1) atoms to form a mixture of distorted corner and edge-sharing SeY2Cu4 octahedra. The corner-sharing octahedral tilt angles range from 1-92°. is represented by the CIF card [CIF]
data_Y(CuSe)3
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   7.777
_cell_length_b   7.777
_cell_length_c   7.777
_cell_angle_alpha   53.765
_cell_angle_beta   53.765
_cell_angle_gamma   53.765
_symmetry_Int_Tables_number   1
_cell_volume   284.173
_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
  Y  Y0  1  0.834  0.834  0.834  1.0
  Y  Y1  1  0.166  0.166  0.166  1.0
  Cu  Cu2  1  0.279  0.969  0.626  1.0
  Cu  Cu3  1  0.626  0.279  0.969  1.0
  Cu  Cu4  1  0.969  0.626  0.279  1.0
  Cu  Cu5  1  0.031  0.374  0.721  1.0
  Cu  Cu6  1  0.374  0.721  0.031  1.0
  Cu  Cu7  1  0.721  0.031  0.374  1.0
  Se  Se8  1  0.089  0.744  0.419  1.0
  Se  Se9  1  0.744  0.419  0.089  1.0
  Se  Se10  1  0.419  0.089  0.744  1.0
  Se  Se11  1  0.581  0.911  0.256  1.0
  Se  Se12  1  0.256  0.581  0.911  1.0
  Se  Se13  1  0.911  0.256  0.581  1.0
[/CIF]
.