The crystal structure described by Be17Hf2 crystallizes in the hexagonal P6_3/mmc 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 Hf(2) atom. In the second Be site, Be(2) is bonded to two equivalent Be(1), four equivalent Be(3), four equivalent Be(4), and two equivalent Hf(2) atoms to form BeHf2Be10 cuboctahedra that share corners with four equivalent Be(2)Hf2Be10 cuboctahedra, corners with eight equivalent Be(3)Hf2Be10 cuboctahedra, corners with ten equivalent Be(4)Hf3Be9 cuboctahedra, edges with four equivalent Be(3)Hf2Be10 cuboctahedra, edges with six equivalent Be(4)Hf3Be9 cuboctahedra, faces with four equivalent Be(4)Hf3Be9 cuboctahedra, faces with six equivalent Be(2)Hf2Be10 cuboctahedra, and faces with eight equivalent Be(3)Hf2Be10 cuboctahedra. 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), one Hf(1), and one Hf(2) atom to form distorted BeHf2Be10 cuboctahedra that share corners with four equivalent Be(2)Hf2Be10 cuboctahedra, corners with eight equivalent Be(4)Hf3Be9 cuboctahedra, corners with twelve equivalent Be(3)Hf2Be10 cuboctahedra,  an edgeedge with one Be(3)Hf2Be10 cuboctahedra, edges with two equivalent Be(2)Hf2Be10 cuboctahedra, edges with two equivalent Be(4)Hf3Be9 cuboctahedra, faces with four equivalent Be(2)Hf2Be10 cuboctahedra, faces with seven equivalent Be(3)Hf2Be10 cuboctahedra, and faces with ten equivalent Be(4)Hf3Be9 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), one Hf(2), and two equivalent Hf(1) atoms to form distorted BeHf3Be9 cuboctahedra that share corners with five equivalent Be(2)Hf2Be10 cuboctahedra, corners with eight equivalent Be(3)Hf2Be10 cuboctahedra, corners with ten equivalent Be(4)Hf3Be9 cuboctahedra, edges with two equivalent Be(3)Hf2Be10 cuboctahedra, edges with three equivalent Be(2)Hf2Be10 cuboctahedra, edges with five equivalent Be(4)Hf3Be9 cuboctahedra, faces with two equivalent Be(2)Hf2Be10 cuboctahedra, faces with eight equivalent Be(4)Hf3Be9 cuboctahedra, and faces with ten equivalent Be(3)Hf2Be10 cuboctahedra. There are two inequivalent Hf sites. In the first Hf site, Hf(1) is bonded in a 18-coordinate geometry to six equivalent Be(3) and twelve equivalent Be(4) atoms. In the second Hf site, Hf(2) is bonded in a 20-coordinate geometry to two equivalent Be(1), six equivalent Be(2), six equivalent Be(3), and six equivalent Be(4) atoms. is represented by the CIF card [CIF]
data_Hf2Be17
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   7.465
_cell_length_b   7.465
_cell_length_c   7.283
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   120.000
_symmetry_Int_Tables_number   1
_cell_volume   351.440
_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
  Hf  Hf0  1  0.000  0.000  0.250  1.0
  Hf  Hf1  1  0.000  0.000  0.750  1.0
  Hf  Hf2  1  0.333  0.667  0.750  1.0
  Hf  Hf3  1  0.667  0.333  0.250  1.0
  Be  Be4  1  0.333  0.667  0.394  1.0
  Be  Be5  1  0.667  0.333  0.606  1.0
  Be  Be6  1  0.667  0.333  0.894  1.0
  Be  Be7  1  0.333  0.667  0.106  1.0
  Be  Be8  1  0.500  0.500  0.500  1.0
  Be  Be9  1  0.500  0.000  0.500  1.0
  Be  Be10  1  0.000  0.500  0.500  1.0
  Be  Be11  1  0.500  0.500  0.000  1.0
  Be  Be12  1  0.500  0.000  0.000  1.0
  Be  Be13  1  0.000  0.500  0.000  1.0
  Be  Be14  1  0.331  0.377  0.250  1.0
  Be  Be15  1  0.623  0.954  0.250  1.0
  Be  Be16  1  0.046  0.669  0.250  1.0
  Be  Be17  1  0.623  0.669  0.250  1.0
  Be  Be18  1  0.046  0.377  0.250  1.0
  Be  Be19  1  0.331  0.954  0.250  1.0
  Be  Be20  1  0.669  0.623  0.750  1.0
  Be  Be21  1  0.377  0.046  0.750  1.0
  Be  Be22  1  0.954  0.331  0.750  1.0
  Be  Be23  1  0.377  0.331  0.750  1.0
  Be  Be24  1  0.954  0.623  0.750  1.0
  Be  Be25  1  0.669  0.046  0.750  1.0
  Be  Be26  1  0.165  0.835  0.513  1.0
  Be  Be27  1  0.165  0.330  0.513  1.0
  Be  Be28  1  0.670  0.835  0.513  1.0
  Be  Be29  1  0.835  0.165  0.487  1.0
  Be  Be30  1  0.835  0.670  0.487  1.0
  Be  Be31  1  0.330  0.165  0.487  1.0
  Be  Be32  1  0.835  0.165  0.013  1.0
  Be  Be33  1  0.835  0.670  0.013  1.0
  Be  Be34  1  0.330  0.165  0.013  1.0
  Be  Be35  1  0.165  0.835  0.987  1.0
  Be  Be36  1  0.165  0.330  0.987  1.0
  Be  Be37  1  0.670  0.835  0.987  1.0
[/CIF]
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The crystal structure described by Be17Hf2 crystallizes in the hexagonal P6_3/mmc 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 Hf(2) atom. In the second Be site, Be(2) is bonded to two equivalent Be(1), four equivalent Be(3), four equivalent Be(4), and two equivalent Hf(2) atoms to form BeHf2Be10 cuboctahedra that share corners with four equivalent Be(2)Hf2Be10 cuboctahedra, corners with eight equivalent Be(3)Hf2Be10 cuboctahedra, corners with ten equivalent Be(4)Hf3Be9 cuboctahedra, edges with four equivalent Be(3)Hf2Be10 cuboctahedra, edges with six equivalent Be(4)Hf3Be9 cuboctahedra, faces with four equivalent Be(4)Hf3Be9 cuboctahedra, faces with six equivalent Be(2)Hf2Be10 cuboctahedra, and faces with eight equivalent Be(3)Hf2Be10 cuboctahedra. 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), one Hf(1), and one Hf(2) atom to form distorted BeHf2Be10 cuboctahedra that share corners with four equivalent Be(2)Hf2Be10 cuboctahedra, corners with eight equivalent Be(4)Hf3Be9 cuboctahedra, corners with twelve equivalent Be(3)Hf2Be10 cuboctahedra,  an edgeedge with one Be(3)Hf2Be10 cuboctahedra, edges with two equivalent Be(2)Hf2Be10 cuboctahedra, edges with two equivalent Be(4)Hf3Be9 cuboctahedra, faces with four equivalent Be(2)Hf2Be10 cuboctahedra, faces with seven equivalent Be(3)Hf2Be10 cuboctahedra, and faces with ten equivalent Be(4)Hf3Be9 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), one Hf(2), and two equivalent Hf(1) atoms to form distorted BeHf3Be9 cuboctahedra that share corners with five equivalent Be(2)Hf2Be10 cuboctahedra, corners with eight equivalent Be(3)Hf2Be10 cuboctahedra, corners with ten equivalent Be(4)Hf3Be9 cuboctahedra, edges with two equivalent Be(3)Hf2Be10 cuboctahedra, edges with three equivalent Be(2)Hf2Be10 cuboctahedra, edges with five equivalent Be(4)Hf3Be9 cuboctahedra, faces with two equivalent Be(2)Hf2Be10 cuboctahedra, faces with eight equivalent Be(4)Hf3Be9 cuboctahedra, and faces with ten equivalent Be(3)Hf2Be10 cuboctahedra. There are two inequivalent Hf sites. In the first Hf site, Hf(1) is bonded in a 18-coordinate geometry to six equivalent Be(3) and twelve equivalent Be(4) atoms. In the second Hf site, Hf(2) is bonded in a 20-coordinate geometry to two equivalent Be(1), six equivalent Be(2), six equivalent Be(3), and six equivalent Be(4) atoms. is represented by the CIF card [CIF]
data_Hf2Be17
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   7.465
_cell_length_b   7.465
_cell_length_c   7.283
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   120.000
_symmetry_Int_Tables_number   1
_cell_volume   351.440
_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
  Hf  Hf0  1  0.000  0.000  0.250  1.0
  Hf  Hf1  1  0.000  0.000  0.750  1.0
  Hf  Hf2  1  0.333  0.667  0.750  1.0
  Hf  Hf3  1  0.667  0.333  0.250  1.0
  Be  Be4  1  0.333  0.667  0.394  1.0
  Be  Be5  1  0.667  0.333  0.606  1.0
  Be  Be6  1  0.667  0.333  0.894  1.0
  Be  Be7  1  0.333  0.667  0.106  1.0
  Be  Be8  1  0.500  0.500  0.500  1.0
  Be  Be9  1  0.500  0.000  0.500  1.0
  Be  Be10  1  0.000  0.500  0.500  1.0
  Be  Be11  1  0.500  0.500  0.000  1.0
  Be  Be12  1  0.500  0.000  0.000  1.0
  Be  Be13  1  0.000  0.500  0.000  1.0
  Be  Be14  1  0.331  0.377  0.250  1.0
  Be  Be15  1  0.623  0.954  0.250  1.0
  Be  Be16  1  0.046  0.669  0.250  1.0
  Be  Be17  1  0.623  0.669  0.250  1.0
  Be  Be18  1  0.046  0.377  0.250  1.0
  Be  Be19  1  0.331  0.954  0.250  1.0
  Be  Be20  1  0.669  0.623  0.750  1.0
  Be  Be21  1  0.377  0.046  0.750  1.0
  Be  Be22  1  0.954  0.331  0.750  1.0
  Be  Be23  1  0.377  0.331  0.750  1.0
  Be  Be24  1  0.954  0.623  0.750  1.0
  Be  Be25  1  0.669  0.046  0.750  1.0
  Be  Be26  1  0.165  0.835  0.513  1.0
  Be  Be27  1  0.165  0.330  0.513  1.0
  Be  Be28  1  0.670  0.835  0.513  1.0
  Be  Be29  1  0.835  0.165  0.487  1.0
  Be  Be30  1  0.835  0.670  0.487  1.0
  Be  Be31  1  0.330  0.165  0.487  1.0
  Be  Be32  1  0.835  0.165  0.013  1.0
  Be  Be33  1  0.835  0.670  0.013  1.0
  Be  Be34  1  0.330  0.165  0.013  1.0
  Be  Be35  1  0.165  0.835  0.987  1.0
  Be  Be36  1  0.165  0.330  0.987  1.0
  Be  Be37  1  0.670  0.835  0.987  1.0
[/CIF]
.