The compound described by Be3Nb crystallizes in the trigonal R-3m space group. There are three inequivalent Be sites. In the first Be site, Be(1) is bonded to six equivalent Be(3) and six equivalent Nb(2) atoms to form BeBe6Nb6 cuboctahedra that share corners with twelve equivalent Be(3)Be7Nb5 cuboctahedra, edges with six equivalent Be(1)Be6Nb6 cuboctahedra, and faces with eighteen equivalent Be(3)Be7Nb5 cuboctahedra. In the second Be site, Be(2) is bonded in a 9-coordinate geometry to six equivalent Be(3) and three equivalent Nb(1) atoms. In the third Be site, Be(3) is bonded to one Be(1), two equivalent Be(2), four equivalent Be(3), two equivalent Nb(1), and three equivalent Nb(2) atoms to form distorted BeBe7Nb5 cuboctahedra that share corners with two equivalent Be(1)Be6Nb6 cuboctahedra, corners with fifteen equivalent Be(3)Be7Nb5 cuboctahedra, edges with eight equivalent Be(3)Be7Nb5 cuboctahedra, faces with three equivalent Be(1)Be6Nb6 cuboctahedra, and faces with eleven equivalent Be(3)Be7Nb5 cuboctahedra. There are two inequivalent Nb sites. In the first Nb site, Nb(1) is bonded in a 20-coordinate geometry to six equivalent Be(2), twelve equivalent Be(3), and two equivalent Nb(2) atoms. In the second Nb site, Nb(2) is bonded in a 16-coordinate geometry to three equivalent Be(1), nine equivalent Be(3), one Nb(1), and three equivalent Nb(2) atoms. is represented by the CIF file [CIF]
data_Be3Nb
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   7.505
_cell_length_b   7.505
_cell_length_c   7.505
_cell_angle_alpha   35.466
_cell_angle_beta   35.466
_cell_angle_gamma   35.466
_symmetry_Int_Tables_number   1
_cell_volume   127.148
_cell_formula_units_Z   3
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  0.500  0.500  0.500  1.0
  Be  Be1  1  0.334  0.334  0.334  1.0
  Be  Be2  1  0.666  0.666  0.666  1.0
  Be  Be3  1  0.584  0.076  0.584  1.0
  Be  Be4  1  0.584  0.584  0.076  1.0
  Be  Be5  1  0.076  0.584  0.584  1.0
  Be  Be6  1  0.924  0.416  0.416  1.0
  Be  Be7  1  0.416  0.924  0.416  1.0
  Be  Be8  1  0.416  0.416  0.924  1.0
  Nb  Nb9  1  0.000  0.000  0.000  1.0
  Nb  Nb10  1  0.140  0.140  0.140  1.0
  Nb  Nb11  1  0.860  0.860  0.860  1.0
[/CIF]
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The compound described by Be3Nb crystallizes in the trigonal R-3m space group. There are three inequivalent Be sites. In the first Be site, Be(1) is bonded to six equivalent Be(3) and six equivalent Nb(2) atoms to form BeBe6Nb6 cuboctahedra that share corners with twelve equivalent Be(3)Be7Nb5 cuboctahedra, edges with six equivalent Be(1)Be6Nb6 cuboctahedra, and faces with eighteen equivalent Be(3)Be7Nb5 cuboctahedra. In the second Be site, Be(2) is bonded in a 9-coordinate geometry to six equivalent Be(3) and three equivalent Nb(1) atoms. In the third Be site, Be(3) is bonded to one Be(1), two equivalent Be(2), four equivalent Be(3), two equivalent Nb(1), and three equivalent Nb(2) atoms to form distorted BeBe7Nb5 cuboctahedra that share corners with two equivalent Be(1)Be6Nb6 cuboctahedra, corners with fifteen equivalent Be(3)Be7Nb5 cuboctahedra, edges with eight equivalent Be(3)Be7Nb5 cuboctahedra, faces with three equivalent Be(1)Be6Nb6 cuboctahedra, and faces with eleven equivalent Be(3)Be7Nb5 cuboctahedra. There are two inequivalent Nb sites. In the first Nb site, Nb(1) is bonded in a 20-coordinate geometry to six equivalent Be(2), twelve equivalent Be(3), and two equivalent Nb(2) atoms. In the second Nb site, Nb(2) is bonded in a 16-coordinate geometry to three equivalent Be(1), nine equivalent Be(3), one Nb(1), and three equivalent Nb(2) atoms. is represented by the CIF file [CIF]
data_Be3Nb
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   7.505
_cell_length_b   7.505
_cell_length_c   7.505
_cell_angle_alpha   35.466
_cell_angle_beta   35.466
_cell_angle_gamma   35.466
_symmetry_Int_Tables_number   1
_cell_volume   127.148
_cell_formula_units_Z   3
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  0.500  0.500  0.500  1.0
  Be  Be1  1  0.334  0.334  0.334  1.0
  Be  Be2  1  0.666  0.666  0.666  1.0
  Be  Be3  1  0.584  0.076  0.584  1.0
  Be  Be4  1  0.584  0.584  0.076  1.0
  Be  Be5  1  0.076  0.584  0.584  1.0
  Be  Be6  1  0.924  0.416  0.416  1.0
  Be  Be7  1  0.416  0.924  0.416  1.0
  Be  Be8  1  0.416  0.416  0.924  1.0
  Nb  Nb9  1  0.000  0.000  0.000  1.0
  Nb  Nb10  1  0.140  0.140  0.140  1.0
  Nb  Nb11  1  0.860  0.860  0.860  1.0
[/CIF]
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