The material structure described by HfAu9 crystallizes in the monoclinic C2/m space group. Hf(1) is bonded to two equivalent Au(4), four equivalent Au(5), and six equivalent Au(3) atoms to form HfAu12 cuboctahedra that share corners with six equivalent Au(2)Au12 cuboctahedra, edges with four equivalent Hf(1)Au12 cuboctahedra, edges with four equivalent Au(1)Au12 cuboctahedra, edges with four equivalent Au(2)Au12 cuboctahedra, faces with two equivalent Hf(1)Au12 cuboctahedra, and faces with two equivalent Au(2)Au12 cuboctahedra. There are five inequivalent Au sites. In the first Au site, Au(1) is bonded to two equivalent Au(5), four equivalent Au(4), and six equivalent Au(2) atoms to form AuAu12 cuboctahedra that share corners with six equivalent Au(3)Hf3Au cuboctahedra, edges with four equivalent Hf(1)Au12 cuboctahedra, edges with four equivalent Au(1)Au12 cuboctahedra, edges with four equivalent Au(2)Au12 cuboctahedra, faces with two equivalent Au(1)Au12 cuboctahedra, and faces with six equivalent Au(2)Au12 cuboctahedra. In the second Au site, Au(2) is bonded to one Au(3), two equivalent Au(2), two equivalent Au(5), three equivalent Au(1), and four equivalent Au(4) atoms to form AuAu12 cuboctahedra that share corners with two equivalent Au(3)Hf3Au cuboctahedra, corners with three equivalent Hf(1)Au12 cuboctahedra, corners with three equivalent Au(2)Au12 cuboctahedra, edges with two equivalent Hf(1)Au12 cuboctahedra, edges with two equivalent Au(1)Au12 cuboctahedra, edges with four equivalent Au(2)Au12 cuboctahedra,  a faceface with one Hf(1)Au12 cuboctahedra, faces with three equivalent Au(1)Au12 cuboctahedra, and faces with five equivalent Au(2)Au12 cuboctahedra. In the third Au site, Au(3) is bonded to three equivalent Hf(1) and one Au(2) atom to form distorted AuHf3Au cuboctahedra that share corners with two equivalent Au(2)Au12 cuboctahedra, corners with three equivalent Au(1)Au12 cuboctahedra, corners with nine equivalent Au(3)Hf3Au cuboctahedra, and edges with three equivalent Au(3)Hf3Au cuboctahedra. In the fourth Au site, Au(4) is bonded in a distorted single-bond geometry to one Hf(1), two equivalent Au(1), and four equivalent Au(2) atoms. In the fifth Au site, Au(5) is bonded in a distorted L-shaped geometry to two equivalent Hf(1), one Au(1), and two equivalent Au(2) atoms. is represented by the CIF card [CIF]
data_HfAu9
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.060
_cell_length_b   5.060
_cell_length_c   9.401
_cell_angle_alpha   88.117
_cell_angle_beta   88.117
_cell_angle_gamma   47.584
_symmetry_Int_Tables_number   1
_cell_volume   177.599
_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
  Hf  Hf0  1  0.500  0.500  0.500  1.0
  Au  Au1  1  0.000  0.000  0.000  1.0
  Au  Au2  1  0.702  0.702  0.901  1.0
  Au  Au3  1  0.203  0.203  0.403  1.0
  Au  Au4  1  0.797  0.797  0.597  1.0
  Au  Au5  1  0.298  0.298  0.099  1.0
  Au  Au6  1  0.400  0.400  0.797  1.0
  Au  Au7  1  0.908  0.908  0.302  1.0
  Au  Au8  1  0.092  0.092  0.698  1.0
  Au  Au9  1  0.600  0.600  0.203  1.0
[/CIF]
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The material structure described by HfAu9 crystallizes in the monoclinic C2/m space group. Hf(1) is bonded to two equivalent Au(4), four equivalent Au(5), and six equivalent Au(3) atoms to form HfAu12 cuboctahedra that share corners with six equivalent Au(2)Au12 cuboctahedra, edges with four equivalent Hf(1)Au12 cuboctahedra, edges with four equivalent Au(1)Au12 cuboctahedra, edges with four equivalent Au(2)Au12 cuboctahedra, faces with two equivalent Hf(1)Au12 cuboctahedra, and faces with two equivalent Au(2)Au12 cuboctahedra. There are five inequivalent Au sites. In the first Au site, Au(1) is bonded to two equivalent Au(5), four equivalent Au(4), and six equivalent Au(2) atoms to form AuAu12 cuboctahedra that share corners with six equivalent Au(3)Hf3Au cuboctahedra, edges with four equivalent Hf(1)Au12 cuboctahedra, edges with four equivalent Au(1)Au12 cuboctahedra, edges with four equivalent Au(2)Au12 cuboctahedra, faces with two equivalent Au(1)Au12 cuboctahedra, and faces with six equivalent Au(2)Au12 cuboctahedra. In the second Au site, Au(2) is bonded to one Au(3), two equivalent Au(2), two equivalent Au(5), three equivalent Au(1), and four equivalent Au(4) atoms to form AuAu12 cuboctahedra that share corners with two equivalent Au(3)Hf3Au cuboctahedra, corners with three equivalent Hf(1)Au12 cuboctahedra, corners with three equivalent Au(2)Au12 cuboctahedra, edges with two equivalent Hf(1)Au12 cuboctahedra, edges with two equivalent Au(1)Au12 cuboctahedra, edges with four equivalent Au(2)Au12 cuboctahedra,  a faceface with one Hf(1)Au12 cuboctahedra, faces with three equivalent Au(1)Au12 cuboctahedra, and faces with five equivalent Au(2)Au12 cuboctahedra. In the third Au site, Au(3) is bonded to three equivalent Hf(1) and one Au(2) atom to form distorted AuHf3Au cuboctahedra that share corners with two equivalent Au(2)Au12 cuboctahedra, corners with three equivalent Au(1)Au12 cuboctahedra, corners with nine equivalent Au(3)Hf3Au cuboctahedra, and edges with three equivalent Au(3)Hf3Au cuboctahedra. In the fourth Au site, Au(4) is bonded in a distorted single-bond geometry to one Hf(1), two equivalent Au(1), and four equivalent Au(2) atoms. In the fifth Au site, Au(5) is bonded in a distorted L-shaped geometry to two equivalent Hf(1), one Au(1), and two equivalent Au(2) atoms. is represented by the CIF card [CIF]
data_HfAu9
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.060
_cell_length_b   5.060
_cell_length_c   9.401
_cell_angle_alpha   88.117
_cell_angle_beta   88.117
_cell_angle_gamma   47.584
_symmetry_Int_Tables_number   1
_cell_volume   177.599
_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
  Hf  Hf0  1  0.500  0.500  0.500  1.0
  Au  Au1  1  0.000  0.000  0.000  1.0
  Au  Au2  1  0.702  0.702  0.901  1.0
  Au  Au3  1  0.203  0.203  0.403  1.0
  Au  Au4  1  0.797  0.797  0.597  1.0
  Au  Au5  1  0.298  0.298  0.099  1.0
  Au  Au6  1  0.400  0.400  0.797  1.0
  Au  Au7  1  0.908  0.908  0.302  1.0
  Au  Au8  1  0.092  0.092  0.698  1.0
  Au  Au9  1  0.600  0.600  0.203  1.0
[/CIF]
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