data_Nb3Cd
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.29
_cell_length_b   5.29
_cell_length_c   5.29
_cell_angle_alpha   90.0
_cell_angle_beta   90.0
_cell_angle_gamma   90.0
_symmetry_Int_Tables_number   1
_chemical_formula_structural   Nb3Cd
_chemical_formula_sum   'Nb6 Cd2'
_cell_volume   148.24
_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
  Nb  Nb2  1  0.65  0.97  0.0  1.0
  Nb  Nb3  1  0.65  0.32  0.0  1.0
  Nb  Nb4  1  0.97  0.0  0.65  1.0
  Nb  Nb5  1  0.0  0.65  0.97  1.0
  Nb  Nb6  1  0.0  0.65  0.32  1.0
  Nb  Nb7  1  0.32  0.0  0.65  1.0
  Cd  Cd0  1  0.65  0.65  0.65  1.0
  Cd  Cd1  1  0.0  0.0  0.0  1.0

data_Nb3Cd
_symmetry_space_group_name_H-M   R3
_cell_length_a   7.48
_cell_length_b   7.48
_cell_length_c   9.17
_cell_angle_alpha   90.0
_cell_angle_beta   90.0
_cell_angle_gamma   120.0
_symmetry_Int_Tables_number   146
_chemical_formula_structural   Nb3Cd
_chemical_formula_sum   'Nb18 Cd6'
_cell_volume   444.71
_cell_formula_units_Z   6
loop_
 _symmetry_equiv_pos_site_id
 _symmetry_equiv_pos_as_xyz
  1  'x, y, z'
  2  '-y, x-y, z'
  3  '-x+y, -x, z'
  4  'x+1/3, y+2/3, z+2/3'
  5  '-y+1/3, x-y+2/3, z+2/3'
  6  '-x+y+1/3, -x+2/3, z+2/3'
  7  'x+2/3, y+1/3, z+1/3'
  8  '-y+2/3, x-y+1/3, z+1/3'
  9  '-x+y+2/3, -x+1/3, z+1/3'
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
  Nb  Nb0  9  0.0  0.68  0.32  1.0
  Nb  Nb1  9  0.1  0.23  0.87  1.0
  Cd  Cd2  3  0.0  0.0  0.0  1.0
  Cd  Cd3  3  0.0  0.0  0.65  1.0

Nb Nb Nb Nb Nb Nb Cd Cd
Nb Nb Nb Nb Nb Nb Cd Cd 0 7 + + o 0 1 o + o 0 6 o o - 1 6 o o - 2 7 + o + 2 5 + o o 2 6 o - o 3 7 o + + 3 4 o o + 3 6 - o o 4 6 - o o 5 6 o - o 
Nb3Cd crystallizes in the trigonal R3 space group. There are two inequivalent Nb sites. In the first Nb site, Nb(1) is bonded in a 1-coordinate geometry to two equivalent Nb(2), one Cd(1), and one Cd(2) atom. There is one shorter (1.87 Å) and one longer (2.54 Å) Nb(1)-Nb(2) bond length. The Nb(1)-Cd(1) bond length is 2.54 Å. The Nb(1)-Cd(2) bond length is 1.88 Å. In the second Nb site, Nb(2) is bonded in a 4-coordinate geometry to two equivalent Nb(1), one Cd(1), and one Cd(2) atom. The Nb(2)-Cd(1) bond length is 2.54 Å. The Nb(2)-Cd(2) bond length is 2.54 Å. There are two inequivalent Cd sites. In the first Cd site, Cd(1) is bonded in a 6-coordinate geometry to three equivalent Nb(1) and three equivalent Nb(2) atoms. In the second Cd site, Cd(2) is bonded in a 3-coordinate geometry to three equivalent Nb(1) and three equivalent Nb(2) atoms.