The crystal structure described by U3Nb crystallizes in the hexagonal P6_3/mmc space group. U(1) is bonded to eight equivalent U(1) and four equivalent Nb(1) atoms to form distorted UU8Nb4 cuboctahedra that share corners with four equivalent Nb(1)U12 cuboctahedra, corners with fourteen equivalent U(1)U8Nb4 cuboctahedra, edges with six equivalent Nb(1)U12 cuboctahedra, edges with twelve equivalent U(1)U8Nb4 cuboctahedra, faces with four equivalent Nb(1)U12 cuboctahedra, and faces with sixteen equivalent U(1)U8Nb4 cuboctahedra. Nb(1) is bonded to twelve equivalent U(1) atoms to form NbU12 cuboctahedra that share corners with six equivalent Nb(1)U12 cuboctahedra, corners with twelve equivalent U(1)U8Nb4 cuboctahedra, edges with eighteen equivalent U(1)U8Nb4 cuboctahedra, faces with eight equivalent Nb(1)U12 cuboctahedra, and faces with twelve equivalent U(1)U8Nb4 cuboctahedra. is represented by the CIF card [CIF]
data_U3Nb
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.931
_cell_length_b   5.931
_cell_length_c   5.475
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   120.000
_symmetry_Int_Tables_number   1
_cell_volume   166.789
_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
  U  U0  1  0.823  0.177  0.750  1.0
  U  U1  1  0.354  0.177  0.750  1.0
  U  U2  1  0.823  0.646  0.750  1.0
  U  U3  1  0.177  0.823  0.250  1.0
  U  U4  1  0.646  0.823  0.250  1.0
  U  U5  1  0.177  0.354  0.250  1.0
  Nb  Nb6  1  0.667  0.333  0.250  1.0
  Nb  Nb7  1  0.333  0.667  0.750  1.0
[/CIF]
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The crystal structure described by U3Nb crystallizes in the hexagonal P6_3/mmc space group. U(1) is bonded to eight equivalent U(1) and four equivalent Nb(1) atoms to form distorted UU8Nb4 cuboctahedra that share corners with four equivalent Nb(1)U12 cuboctahedra, corners with fourteen equivalent U(1)U8Nb4 cuboctahedra, edges with six equivalent Nb(1)U12 cuboctahedra, edges with twelve equivalent U(1)U8Nb4 cuboctahedra, faces with four equivalent Nb(1)U12 cuboctahedra, and faces with sixteen equivalent U(1)U8Nb4 cuboctahedra. Nb(1) is bonded to twelve equivalent U(1) atoms to form NbU12 cuboctahedra that share corners with six equivalent Nb(1)U12 cuboctahedra, corners with twelve equivalent U(1)U8Nb4 cuboctahedra, edges with eighteen equivalent U(1)U8Nb4 cuboctahedra, faces with eight equivalent Nb(1)U12 cuboctahedra, and faces with twelve equivalent U(1)U8Nb4 cuboctahedra. is represented by the CIF card [CIF]
data_U3Nb
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.931
_cell_length_b   5.931
_cell_length_c   5.475
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   120.000
_symmetry_Int_Tables_number   1
_cell_volume   166.789
_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
  U  U0  1  0.823  0.177  0.750  1.0
  U  U1  1  0.354  0.177  0.750  1.0
  U  U2  1  0.823  0.646  0.750  1.0
  U  U3  1  0.177  0.823  0.250  1.0
  U  U4  1  0.646  0.823  0.250  1.0
  U  U5  1  0.177  0.354  0.250  1.0
  Nb  Nb6  1  0.667  0.333  0.250  1.0
  Nb  Nb7  1  0.333  0.667  0.750  1.0
[/CIF]
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