The structure described by La3Nb is beta Cu3Ti-like structured and crystallizes in the tetragonal I4/mmm space group. There are two inequivalent La sites. In the first La site, La(1) is bonded to four equivalent La(1), four equivalent La(2), and four equivalent Nb(1) atoms to form distorted LaLa8Nb4 cuboctahedra that share corners with twelve equivalent La(1)La8Nb4 cuboctahedra, edges with eight equivalent La(1)La8Nb4 cuboctahedra, edges with eight equivalent La(2)La8Nb4 cuboctahedra, edges with eight equivalent Nb(1)La12 cuboctahedra, faces with four equivalent La(2)La8Nb4 cuboctahedra, faces with four equivalent Nb(1)La12 cuboctahedra, and faces with ten equivalent La(1)La8Nb4 cuboctahedra. In the second La site, La(2) is bonded to eight equivalent La(1) and four equivalent Nb(1) atoms to form LaLa8Nb4 cuboctahedra that share corners with four equivalent La(2)La8Nb4 cuboctahedra, corners with eight equivalent Nb(1)La12 cuboctahedra, edges with eight equivalent La(2)La8Nb4 cuboctahedra, edges with sixteen equivalent La(1)La8Nb4 cuboctahedra, faces with four equivalent La(2)La8Nb4 cuboctahedra, faces with six equivalent Nb(1)La12 cuboctahedra, and faces with eight equivalent La(1)La8Nb4 cuboctahedra. Nb(1) is bonded to four equivalent La(2) and eight equivalent La(1) atoms to form NbLa12 cuboctahedra that share corners with four equivalent Nb(1)La12 cuboctahedra, corners with eight equivalent La(2)La8Nb4 cuboctahedra, edges with eight equivalent Nb(1)La12 cuboctahedra, edges with sixteen equivalent La(1)La8Nb4 cuboctahedra, faces with four equivalent Nb(1)La12 cuboctahedra, faces with six equivalent La(2)La8Nb4 cuboctahedra, and faces with eight equivalent La(1)La8Nb4 cuboctahedra. is represented by the Crystallographic Information File (CIF) [CIF]
data_La3Nb
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.939
_cell_length_b   5.939
_cell_length_c   5.939
_cell_angle_alpha   130.853
_cell_angle_beta   130.853
_cell_angle_gamma   72.047
_symmetry_Int_Tables_number   1
_cell_volume   117.206
_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
  La  La0  1  0.750  0.250  0.500  1.0
  La  La1  1  0.250  0.750  0.500  1.0
  La  La2  1  0.500  0.500  0.000  1.0
  Nb  Nb3  1  0.000  0.000  0.000  1.0
[/CIF]
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The structure described by La3Nb is beta Cu3Ti-like structured and crystallizes in the tetragonal I4/mmm space group. There are two inequivalent La sites. In the first La site, La(1) is bonded to four equivalent La(1), four equivalent La(2), and four equivalent Nb(1) atoms to form distorted LaLa8Nb4 cuboctahedra that share corners with twelve equivalent La(1)La8Nb4 cuboctahedra, edges with eight equivalent La(1)La8Nb4 cuboctahedra, edges with eight equivalent La(2)La8Nb4 cuboctahedra, edges with eight equivalent Nb(1)La12 cuboctahedra, faces with four equivalent La(2)La8Nb4 cuboctahedra, faces with four equivalent Nb(1)La12 cuboctahedra, and faces with ten equivalent La(1)La8Nb4 cuboctahedra. In the second La site, La(2) is bonded to eight equivalent La(1) and four equivalent Nb(1) atoms to form LaLa8Nb4 cuboctahedra that share corners with four equivalent La(2)La8Nb4 cuboctahedra, corners with eight equivalent Nb(1)La12 cuboctahedra, edges with eight equivalent La(2)La8Nb4 cuboctahedra, edges with sixteen equivalent La(1)La8Nb4 cuboctahedra, faces with four equivalent La(2)La8Nb4 cuboctahedra, faces with six equivalent Nb(1)La12 cuboctahedra, and faces with eight equivalent La(1)La8Nb4 cuboctahedra. Nb(1) is bonded to four equivalent La(2) and eight equivalent La(1) atoms to form NbLa12 cuboctahedra that share corners with four equivalent Nb(1)La12 cuboctahedra, corners with eight equivalent La(2)La8Nb4 cuboctahedra, edges with eight equivalent Nb(1)La12 cuboctahedra, edges with sixteen equivalent La(1)La8Nb4 cuboctahedra, faces with four equivalent Nb(1)La12 cuboctahedra, faces with six equivalent La(2)La8Nb4 cuboctahedra, and faces with eight equivalent La(1)La8Nb4 cuboctahedra. is represented by the Crystallographic Information File (CIF) [CIF]
data_La3Nb
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.939
_cell_length_b   5.939
_cell_length_c   5.939
_cell_angle_alpha   130.853
_cell_angle_beta   130.853
_cell_angle_gamma   72.047
_symmetry_Int_Tables_number   1
_cell_volume   117.206
_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
  La  La0  1  0.750  0.250  0.500  1.0
  La  La1  1  0.250  0.750  0.500  1.0
  La  La2  1  0.500  0.500  0.000  1.0
  Nb  Nb3  1  0.000  0.000  0.000  1.0
[/CIF]
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