The compound described by Be17Nb2 crystallizes in the trigonal R-3m space group. There are four inequivalent Be sites. In the first Be site, Be(1) is bonded in a 14-coordinate geometry to one Be(1), three equivalent Be(2), three equivalent Be(4), six equivalent Be(3), and one Nb(1) atom. In the second Be site, Be(2) is bonded in a 10-coordinate geometry to two equivalent Be(1), four equivalent Be(3), four equivalent Be(4), and two equivalent Nb(1) atoms. In the third Be site, Be(3) is bonded to two equivalent Be(1), two equivalent Be(2), two equivalent Be(3), four equivalent Be(4), and two equivalent Nb(1) atoms to form distorted BeBe10Nb2 cuboctahedra that share corners with eight equivalent Be(4)Be9Nb3 cuboctahedra, corners with twelve equivalent Be(3)Be10Nb2 cuboctahedra,  an edgeedge with one Be(3)Be10Nb2 cuboctahedra, edges with two equivalent Be(4)Be9Nb3 cuboctahedra, faces with seven equivalent Be(3)Be10Nb2 cuboctahedra, and faces with ten equivalent Be(4)Be9Nb3 cuboctahedra. In the fourth Be site, Be(4) is bonded to one Be(1), two equivalent Be(2), two equivalent Be(4), four equivalent Be(3), and three equivalent Nb(1) atoms to form distorted BeBe9Nb3 cuboctahedra that share corners with eight equivalent Be(3)Be10Nb2 cuboctahedra, corners with ten equivalent Be(4)Be9Nb3 cuboctahedra, edges with two equivalent Be(3)Be10Nb2 cuboctahedra, edges with five equivalent Be(4)Be9Nb3 cuboctahedra, faces with seven equivalent Be(4)Be9Nb3 cuboctahedra, and faces with ten equivalent Be(3)Be10Nb2 cuboctahedra. Nb(1) is bonded in a 19-coordinate geometry to one Be(1), three equivalent Be(2), six equivalent Be(3), and nine equivalent Be(4) atoms. is represented by the Crystallographic Information File (CIF) [CIF]
data_Be17Nb2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.567
_cell_length_b   5.567
_cell_length_c   5.567
_cell_angle_alpha   83.052
_cell_angle_beta   83.052
_cell_angle_gamma   83.051
_symmetry_Int_Tables_number   1
_cell_volume   168.984
_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
  Be  Be0  1  0.401  0.401  0.401  1.0
  Be  Be1  1  0.599  0.599  0.599  1.0
  Be  Be2  1  0.500  0.500  0.000  1.0
  Be  Be3  1  0.000  0.500  0.500  1.0
  Be  Be4  1  0.500  0.000  0.500  1.0
  Be  Be5  1  0.795  0.500  0.205  1.0
  Be  Be6  1  0.205  0.795  0.500  1.0
  Be  Be7  1  0.500  0.205  0.795  1.0
  Be  Be8  1  0.205  0.500  0.795  1.0
  Be  Be9  1  0.795  0.205  0.500  1.0
  Be  Be10  1  0.500  0.795  0.205  1.0
  Be  Be11  1  0.153  0.661  0.153  1.0
  Be  Be12  1  0.153  0.153  0.661  1.0
  Be  Be13  1  0.661  0.153  0.153  1.0
  Be  Be14  1  0.339  0.847  0.847  1.0
  Be  Be15  1  0.847  0.339  0.847  1.0
  Be  Be16  1  0.847  0.847  0.339  1.0
  Nb  Nb17  1  0.160  0.160  0.160  1.0
  Nb  Nb18  1  0.840  0.840  0.840  1.0
[/CIF]
.
The compound described by Be17Nb2 crystallizes in the trigonal R-3m space group. There are four inequivalent Be sites. In the first Be site, Be(1) is bonded in a 14-coordinate geometry to one Be(1), three equivalent Be(2), three equivalent Be(4), six equivalent Be(3), and one Nb(1) atom. In the second Be site, Be(2) is bonded in a 10-coordinate geometry to two equivalent Be(1), four equivalent Be(3), four equivalent Be(4), and two equivalent Nb(1) atoms. In the third Be site, Be(3) is bonded to two equivalent Be(1), two equivalent Be(2), two equivalent Be(3), four equivalent Be(4), and two equivalent Nb(1) atoms to form distorted BeBe10Nb2 cuboctahedra that share corners with eight equivalent Be(4)Be9Nb3 cuboctahedra, corners with twelve equivalent Be(3)Be10Nb2 cuboctahedra,  an edgeedge with one Be(3)Be10Nb2 cuboctahedra, edges with two equivalent Be(4)Be9Nb3 cuboctahedra, faces with seven equivalent Be(3)Be10Nb2 cuboctahedra, and faces with ten equivalent Be(4)Be9Nb3 cuboctahedra. In the fourth Be site, Be(4) is bonded to one Be(1), two equivalent Be(2), two equivalent Be(4), four equivalent Be(3), and three equivalent Nb(1) atoms to form distorted BeBe9Nb3 cuboctahedra that share corners with eight equivalent Be(3)Be10Nb2 cuboctahedra, corners with ten equivalent Be(4)Be9Nb3 cuboctahedra, edges with two equivalent Be(3)Be10Nb2 cuboctahedra, edges with five equivalent Be(4)Be9Nb3 cuboctahedra, faces with seven equivalent Be(4)Be9Nb3 cuboctahedra, and faces with ten equivalent Be(3)Be10Nb2 cuboctahedra. Nb(1) is bonded in a 19-coordinate geometry to one Be(1), three equivalent Be(2), six equivalent Be(3), and nine equivalent Be(4) atoms. is represented by the Crystallographic Information File (CIF) [CIF]
data_Be17Nb2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.567
_cell_length_b   5.567
_cell_length_c   5.567
_cell_angle_alpha   83.052
_cell_angle_beta   83.052
_cell_angle_gamma   83.051
_symmetry_Int_Tables_number   1
_cell_volume   168.984
_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
  Be  Be0  1  0.401  0.401  0.401  1.0
  Be  Be1  1  0.599  0.599  0.599  1.0
  Be  Be2  1  0.500  0.500  0.000  1.0
  Be  Be3  1  0.000  0.500  0.500  1.0
  Be  Be4  1  0.500  0.000  0.500  1.0
  Be  Be5  1  0.795  0.500  0.205  1.0
  Be  Be6  1  0.205  0.795  0.500  1.0
  Be  Be7  1  0.500  0.205  0.795  1.0
  Be  Be8  1  0.205  0.500  0.795  1.0
  Be  Be9  1  0.795  0.205  0.500  1.0
  Be  Be10  1  0.500  0.795  0.205  1.0
  Be  Be11  1  0.153  0.661  0.153  1.0
  Be  Be12  1  0.153  0.153  0.661  1.0
  Be  Be13  1  0.661  0.153  0.153  1.0
  Be  Be14  1  0.339  0.847  0.847  1.0
  Be  Be15  1  0.847  0.339  0.847  1.0
  Be  Be16  1  0.847  0.847  0.339  1.0
  Nb  Nb17  1  0.160  0.160  0.160  1.0
  Nb  Nb18  1  0.840  0.840  0.840  1.0
[/CIF]
.