The compound described by U3Y is beta Cu3Ti-like structured and crystallizes in the tetragonal I4/mmm space group. There are two inequivalent U sites. In the first U site, U(1) is bonded to four equivalent U(1), four equivalent U(2), and four equivalent Y(1) atoms to form UY4U8 cuboctahedra that share corners with twelve equivalent U(1)Y4U8 cuboctahedra, edges with eight equivalent U(1)Y4U8 cuboctahedra, edges with eight equivalent U(2)Y4U8 cuboctahedra, edges with eight equivalent Y(1)U12 cuboctahedra, faces with four equivalent U(2)Y4U8 cuboctahedra, faces with four equivalent Y(1)U12 cuboctahedra, and faces with ten equivalent U(1)Y4U8 cuboctahedra. In the second U site, U(2) is bonded to eight equivalent U(1) and four equivalent Y(1) atoms to form distorted UY4U8 cuboctahedra that share corners with four equivalent U(2)Y4U8 cuboctahedra, corners with eight equivalent Y(1)U12 cuboctahedra, edges with eight equivalent U(2)Y4U8 cuboctahedra, edges with sixteen equivalent U(1)Y4U8 cuboctahedra, faces with four equivalent U(2)Y4U8 cuboctahedra, faces with six equivalent Y(1)U12 cuboctahedra, and faces with eight equivalent U(1)Y4U8 cuboctahedra. Y(1) is bonded to four equivalent U(2) and eight equivalent U(1) atoms to form YU12 cuboctahedra that share corners with four equivalent Y(1)U12 cuboctahedra, corners with eight equivalent U(2)Y4U8 cuboctahedra, edges with eight equivalent Y(1)U12 cuboctahedra, edges with sixteen equivalent U(1)Y4U8 cuboctahedra, faces with four equivalent Y(1)U12 cuboctahedra, faces with six equivalent U(2)Y4U8 cuboctahedra, and faces with eight equivalent U(1)Y4U8 cuboctahedra. is represented by the CIF card [CIF]
data_YU3
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.695
_cell_length_b   5.695
_cell_length_c   5.695
_cell_angle_alpha   134.509
_cell_angle_beta   134.509
_cell_angle_gamma   66.294
_symmetry_Int_Tables_number   1
_cell_volume   92.487
_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  0.000  0.000  0.000  1.0
  U  U1  1  0.750  0.250  0.500  1.0
  U  U2  1  0.250  0.750  0.500  1.0
  U  U3  1  0.500  0.500  0.000  1.0
[/CIF]
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The compound described by U3Y is beta Cu3Ti-like structured and crystallizes in the tetragonal I4/mmm space group. There are two inequivalent U sites. In the first U site, U(1) is bonded to four equivalent U(1), four equivalent U(2), and four equivalent Y(1) atoms to form UY4U8 cuboctahedra that share corners with twelve equivalent U(1)Y4U8 cuboctahedra, edges with eight equivalent U(1)Y4U8 cuboctahedra, edges with eight equivalent U(2)Y4U8 cuboctahedra, edges with eight equivalent Y(1)U12 cuboctahedra, faces with four equivalent U(2)Y4U8 cuboctahedra, faces with four equivalent Y(1)U12 cuboctahedra, and faces with ten equivalent U(1)Y4U8 cuboctahedra. In the second U site, U(2) is bonded to eight equivalent U(1) and four equivalent Y(1) atoms to form distorted UY4U8 cuboctahedra that share corners with four equivalent U(2)Y4U8 cuboctahedra, corners with eight equivalent Y(1)U12 cuboctahedra, edges with eight equivalent U(2)Y4U8 cuboctahedra, edges with sixteen equivalent U(1)Y4U8 cuboctahedra, faces with four equivalent U(2)Y4U8 cuboctahedra, faces with six equivalent Y(1)U12 cuboctahedra, and faces with eight equivalent U(1)Y4U8 cuboctahedra. Y(1) is bonded to four equivalent U(2) and eight equivalent U(1) atoms to form YU12 cuboctahedra that share corners with four equivalent Y(1)U12 cuboctahedra, corners with eight equivalent U(2)Y4U8 cuboctahedra, edges with eight equivalent Y(1)U12 cuboctahedra, edges with sixteen equivalent U(1)Y4U8 cuboctahedra, faces with four equivalent Y(1)U12 cuboctahedra, faces with six equivalent U(2)Y4U8 cuboctahedra, and faces with eight equivalent U(1)Y4U8 cuboctahedra. is represented by the CIF card [CIF]
data_YU3
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.695
_cell_length_b   5.695
_cell_length_c   5.695
_cell_angle_alpha   134.509
_cell_angle_beta   134.509
_cell_angle_gamma   66.294
_symmetry_Int_Tables_number   1
_cell_volume   92.487
_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  0.000  0.000  0.000  1.0
  U  U1  1  0.750  0.250  0.500  1.0
  U  U2  1  0.250  0.750  0.500  1.0
  U  U3  1  0.500  0.500  0.000  1.0
[/CIF]
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