The crystal structure described by Nb3Co8Al is Hexagonal Laves-derived structured and crystallizes in the trigonal R3m space group. There are three inequivalent Nb sites. In the first Nb site, Nb(1) is bonded in a 16-coordinate geometry to one Nb(3), three equivalent Nb(2), three equivalent Co(1), three equivalent Co(4), and six equivalent Co(2) atoms. In the second Nb site, Nb(2) is bonded in a 16-coordinate geometry to three equivalent Nb(1), three equivalent Co(2), three equivalent Co(4), six equivalent Co(1), and one Al(1) atom. In the third Nb site, Nb(3) is bonded in a 16-coordinate geometry to one Nb(1), three equivalent Co(1), three equivalent Co(3), six equivalent Co(2), and three equivalent Al(1) atoms. There are four inequivalent Co sites. In the first Co site, Co(1) is bonded to one Nb(1), one Nb(3), two equivalent Nb(2), one Co(3), one Co(4), four equivalent Co(1), and two equivalent Al(1) atoms to form CoNb4Al2Co6 cuboctahedra that share corners with two equivalent Co(3)Nb3Al3Co6 cuboctahedra, corners with two equivalent Co(4)Nb6Co6 cuboctahedra, corners with four equivalent Co(1)Nb4Al2Co6 cuboctahedra, corners with ten equivalent Co(2)Nb5AlCo6 cuboctahedra, edges with two equivalent Co(1)Nb4Al2Co6 cuboctahedra, edges with four equivalent Co(2)Nb5AlCo6 cuboctahedra, faces with three equivalent Co(3)Nb3Al3Co6 cuboctahedra, faces with three equivalent Co(4)Nb6Co6 cuboctahedra, faces with four equivalent Co(2)Nb5AlCo6 cuboctahedra, and faces with eight equivalent Co(1)Nb4Al2Co6 cuboctahedra. In the second Co site, Co(2) is bonded to one Nb(2), two equivalent Nb(1), two equivalent Nb(3), one Co(3), one Co(4), four equivalent Co(2), and one Al(1) atom to form CoNb5AlCo6 cuboctahedra that share corners with two equivalent Co(3)Nb3Al3Co6 cuboctahedra, corners with two equivalent Co(4)Nb6Co6 cuboctahedra, corners with four equivalent Co(2)Nb5AlCo6 cuboctahedra, corners with ten equivalent Co(1)Nb4Al2Co6 cuboctahedra, edges with two equivalent Co(2)Nb5AlCo6 cuboctahedra, edges with four equivalent Co(1)Nb4Al2Co6 cuboctahedra, faces with three equivalent Co(3)Nb3Al3Co6 cuboctahedra, faces with three equivalent Co(4)Nb6Co6 cuboctahedra, faces with four equivalent Co(1)Nb4Al2Co6 cuboctahedra, and faces with eight equivalent Co(2)Nb5AlCo6 cuboctahedra. In the third Co site, Co(3) is bonded to three equivalent Nb(3), three equivalent Co(1), three equivalent Co(2), and three equivalent Al(1) atoms to form CoNb3Al3Co6 cuboctahedra that share corners with six equivalent Co(1)Nb4Al2Co6 cuboctahedra, corners with six equivalent Co(2)Nb5AlCo6 cuboctahedra, corners with six equivalent Co(4)Nb6Co6 cuboctahedra, edges with six equivalent Co(3)Nb3Al3Co6 cuboctahedra, faces with nine equivalent Co(1)Nb4Al2Co6 cuboctahedra, and faces with nine equivalent Co(2)Nb5AlCo6 cuboctahedra. In the fourth Co site, Co(4) is bonded to three equivalent Nb(1), three equivalent Nb(2), three equivalent Co(1), and three equivalent Co(2) atoms to form CoNb6Co6 cuboctahedra that share corners with six equivalent Co(3)Nb3Al3Co6 cuboctahedra, corners with six equivalent Co(1)Nb4Al2Co6 cuboctahedra, corners with six equivalent Co(2)Nb5AlCo6 cuboctahedra, edges with six equivalent Co(4)Nb6Co6 cuboctahedra, faces with nine equivalent Co(1)Nb4Al2Co6 cuboctahedra, and faces with nine equivalent Co(2)Nb5AlCo6 cuboctahedra. Al(1) is bonded in a 16-coordinate geometry to one Nb(2), three equivalent Nb(3), three equivalent Co(2), three equivalent Co(3), and six equivalent Co(1) atoms. is represented by the CIF file [CIF]
data_Nb3AlCo8
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   8.206
_cell_length_b   8.206
_cell_length_c   8.206
_cell_angle_alpha   33.595
_cell_angle_beta   33.595
_cell_angle_gamma   33.595
_symmetry_Int_Tables_number   1
_cell_volume   150.720
_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
  Nb  Nb0  1  0.623  0.623  0.623  1.0
  Nb  Nb1  1  0.003  0.003  0.003  1.0
  Nb  Nb2  1  0.498  0.498  0.498  1.0
  Al  Al3  1  0.126  0.126  0.126  1.0
  Co  Co4  1  0.564  0.060  0.564  1.0
  Co  Co5  1  0.064  0.561  0.064  1.0
  Co  Co6  1  0.060  0.564  0.564  1.0
  Co  Co7  1  0.561  0.064  0.064  1.0
  Co  Co8  1  0.812  0.812  0.812  1.0
  Co  Co9  1  0.312  0.312  0.312  1.0
  Co  Co10  1  0.564  0.564  0.060  1.0
  Co  Co11  1  0.064  0.064  0.561  1.0
[/CIF]
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The crystal structure described by Nb3Co8Al is Hexagonal Laves-derived structured and crystallizes in the trigonal R3m space group. There are three inequivalent Nb sites. In the first Nb site, Nb(1) is bonded in a 16-coordinate geometry to one Nb(3), three equivalent Nb(2), three equivalent Co(1), three equivalent Co(4), and six equivalent Co(2) atoms. In the second Nb site, Nb(2) is bonded in a 16-coordinate geometry to three equivalent Nb(1), three equivalent Co(2), three equivalent Co(4), six equivalent Co(1), and one Al(1) atom. In the third Nb site, Nb(3) is bonded in a 16-coordinate geometry to one Nb(1), three equivalent Co(1), three equivalent Co(3), six equivalent Co(2), and three equivalent Al(1) atoms. There are four inequivalent Co sites. In the first Co site, Co(1) is bonded to one Nb(1), one Nb(3), two equivalent Nb(2), one Co(3), one Co(4), four equivalent Co(1), and two equivalent Al(1) atoms to form CoNb4Al2Co6 cuboctahedra that share corners with two equivalent Co(3)Nb3Al3Co6 cuboctahedra, corners with two equivalent Co(4)Nb6Co6 cuboctahedra, corners with four equivalent Co(1)Nb4Al2Co6 cuboctahedra, corners with ten equivalent Co(2)Nb5AlCo6 cuboctahedra, edges with two equivalent Co(1)Nb4Al2Co6 cuboctahedra, edges with four equivalent Co(2)Nb5AlCo6 cuboctahedra, faces with three equivalent Co(3)Nb3Al3Co6 cuboctahedra, faces with three equivalent Co(4)Nb6Co6 cuboctahedra, faces with four equivalent Co(2)Nb5AlCo6 cuboctahedra, and faces with eight equivalent Co(1)Nb4Al2Co6 cuboctahedra. In the second Co site, Co(2) is bonded to one Nb(2), two equivalent Nb(1), two equivalent Nb(3), one Co(3), one Co(4), four equivalent Co(2), and one Al(1) atom to form CoNb5AlCo6 cuboctahedra that share corners with two equivalent Co(3)Nb3Al3Co6 cuboctahedra, corners with two equivalent Co(4)Nb6Co6 cuboctahedra, corners with four equivalent Co(2)Nb5AlCo6 cuboctahedra, corners with ten equivalent Co(1)Nb4Al2Co6 cuboctahedra, edges with two equivalent Co(2)Nb5AlCo6 cuboctahedra, edges with four equivalent Co(1)Nb4Al2Co6 cuboctahedra, faces with three equivalent Co(3)Nb3Al3Co6 cuboctahedra, faces with three equivalent Co(4)Nb6Co6 cuboctahedra, faces with four equivalent Co(1)Nb4Al2Co6 cuboctahedra, and faces with eight equivalent Co(2)Nb5AlCo6 cuboctahedra. In the third Co site, Co(3) is bonded to three equivalent Nb(3), three equivalent Co(1), three equivalent Co(2), and three equivalent Al(1) atoms to form CoNb3Al3Co6 cuboctahedra that share corners with six equivalent Co(1)Nb4Al2Co6 cuboctahedra, corners with six equivalent Co(2)Nb5AlCo6 cuboctahedra, corners with six equivalent Co(4)Nb6Co6 cuboctahedra, edges with six equivalent Co(3)Nb3Al3Co6 cuboctahedra, faces with nine equivalent Co(1)Nb4Al2Co6 cuboctahedra, and faces with nine equivalent Co(2)Nb5AlCo6 cuboctahedra. In the fourth Co site, Co(4) is bonded to three equivalent Nb(1), three equivalent Nb(2), three equivalent Co(1), and three equivalent Co(2) atoms to form CoNb6Co6 cuboctahedra that share corners with six equivalent Co(3)Nb3Al3Co6 cuboctahedra, corners with six equivalent Co(1)Nb4Al2Co6 cuboctahedra, corners with six equivalent Co(2)Nb5AlCo6 cuboctahedra, edges with six equivalent Co(4)Nb6Co6 cuboctahedra, faces with nine equivalent Co(1)Nb4Al2Co6 cuboctahedra, and faces with nine equivalent Co(2)Nb5AlCo6 cuboctahedra. Al(1) is bonded in a 16-coordinate geometry to one Nb(2), three equivalent Nb(3), three equivalent Co(2), three equivalent Co(3), and six equivalent Co(1) atoms. is represented by the CIF file [CIF]
data_Nb3AlCo8
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   8.206
_cell_length_b   8.206
_cell_length_c   8.206
_cell_angle_alpha   33.595
_cell_angle_beta   33.595
_cell_angle_gamma   33.595
_symmetry_Int_Tables_number   1
_cell_volume   150.720
_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
  Nb  Nb0  1  0.623  0.623  0.623  1.0
  Nb  Nb1  1  0.003  0.003  0.003  1.0
  Nb  Nb2  1  0.498  0.498  0.498  1.0
  Al  Al3  1  0.126  0.126  0.126  1.0
  Co  Co4  1  0.564  0.060  0.564  1.0
  Co  Co5  1  0.064  0.561  0.064  1.0
  Co  Co6  1  0.060  0.564  0.564  1.0
  Co  Co7  1  0.561  0.064  0.064  1.0
  Co  Co8  1  0.812  0.812  0.812  1.0
  Co  Co9  1  0.312  0.312  0.312  1.0
  Co  Co10  1  0.564  0.564  0.060  1.0
  Co  Co11  1  0.064  0.064  0.561  1.0
[/CIF]
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