The compound described by UY2Se3 is Caswellsilverite-like structured and crystallizes in the trigonal P-3m1 space group. U(1) is bonded to six equivalent Se(1) atoms to form USe6 octahedra that share corners with six equivalent Y(1)Se6 octahedra, edges with six equivalent U(1)Se6 octahedra, and edges with six equivalent Y(1)Se6 octahedra. The corner-sharing octahedral tilt angles are 2°. Y(1) is bonded to three equivalent Se(1) and three equivalent Se(2) atoms to form YSe6 octahedra that share corners with three equivalent U(1)Se6 octahedra, corners with three equivalent Y(1)Se6 octahedra, edges with three equivalent U(1)Se6 octahedra, and edges with nine equivalent Y(1)Se6 octahedra. The corner-sharing octahedral tilt angles range from 0-2°. There are two inequivalent Se sites. In the first Se site, Se(1) is bonded to three equivalent U(1) and three equivalent Y(1) atoms to form SeY3U3 octahedra that share corners with three equivalent Se(1)Y3U3 octahedra, corners with three equivalent Se(2)Y6 octahedra, edges with three equivalent Se(2)Y6 octahedra, and edges with nine equivalent Se(1)Y3U3 octahedra. The corner-sharing octahedral tilt angles range from 0-2°. In the second Se site, Se(2) is bonded to six equivalent Y(1) atoms to form SeY6 octahedra that share corners with six equivalent Se(1)Y3U3 octahedra, edges with six equivalent Se(1)Y3U3 octahedra, and edges with six equivalent Se(2)Y6 octahedra. The corner-sharing octahedral tilt angles are 2°. is represented by the CIF card [CIF]
data_Y2USe3
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   4.012
_cell_length_b   4.012
_cell_length_c   10.273
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   120.000
_symmetry_Int_Tables_number   1
_cell_volume   143.201
_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
  Y  Y0  1  0.333  0.667  0.673  1.0
  Y  Y1  1  0.667  0.333  0.327  1.0
  U  U2  1  0.000  0.000  0.000  1.0
  Se  Se3  1  0.333  0.667  0.168  1.0
  Se  Se4  1  0.667  0.333  0.832  1.0
  Se  Se5  1  0.000  0.000  0.500  1.0
[/CIF]
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The compound described by UY2Se3 is Caswellsilverite-like structured and crystallizes in the trigonal P-3m1 space group. U(1) is bonded to six equivalent Se(1) atoms to form USe6 octahedra that share corners with six equivalent Y(1)Se6 octahedra, edges with six equivalent U(1)Se6 octahedra, and edges with six equivalent Y(1)Se6 octahedra. The corner-sharing octahedral tilt angles are 2°. Y(1) is bonded to three equivalent Se(1) and three equivalent Se(2) atoms to form YSe6 octahedra that share corners with three equivalent U(1)Se6 octahedra, corners with three equivalent Y(1)Se6 octahedra, edges with three equivalent U(1)Se6 octahedra, and edges with nine equivalent Y(1)Se6 octahedra. The corner-sharing octahedral tilt angles range from 0-2°. There are two inequivalent Se sites. In the first Se site, Se(1) is bonded to three equivalent U(1) and three equivalent Y(1) atoms to form SeY3U3 octahedra that share corners with three equivalent Se(1)Y3U3 octahedra, corners with three equivalent Se(2)Y6 octahedra, edges with three equivalent Se(2)Y6 octahedra, and edges with nine equivalent Se(1)Y3U3 octahedra. The corner-sharing octahedral tilt angles range from 0-2°. In the second Se site, Se(2) is bonded to six equivalent Y(1) atoms to form SeY6 octahedra that share corners with six equivalent Se(1)Y3U3 octahedra, edges with six equivalent Se(1)Y3U3 octahedra, and edges with six equivalent Se(2)Y6 octahedra. The corner-sharing octahedral tilt angles are 2°. is represented by the CIF card [CIF]
data_Y2USe3
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   4.012
_cell_length_b   4.012
_cell_length_c   10.273
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   120.000
_symmetry_Int_Tables_number   1
_cell_volume   143.201
_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
  Y  Y0  1  0.333  0.667  0.673  1.0
  Y  Y1  1  0.667  0.333  0.327  1.0
  U  U2  1  0.000  0.000  0.000  1.0
  Se  Se3  1  0.333  0.667  0.168  1.0
  Se  Se4  1  0.667  0.333  0.832  1.0
  Se  Se5  1  0.000  0.000  0.500  1.0
[/CIF]
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