data_HfB2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   7.58
_cell_length_b   7.58
_cell_length_c   7.58
_cell_angle_alpha   60.0
_cell_angle_beta   60.0
_cell_angle_gamma   60.0
_symmetry_Int_Tables_number   1
_chemical_formula_structural   HfB2
_chemical_formula_sum   'Hf8 B16'
_cell_volume   307.68
_cell_formula_units_Z   8
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  Hf16  1  0.96  0.96  0.76  1.0
  Hf  Hf17  1  0.76  0.76  0.76  1.0
  Hf  Hf18  1  0.96  0.76  0.96  1.0
  Hf  Hf19  1  0.76  0.96  0.96  1.0
  Hf  Hf20  1  0.44  0.44  0.64  1.0
  Hf  Hf21  1  0.64  0.64  0.64  1.0
  Hf  Hf22  1  0.44  0.64  0.44  1.0
  Hf  Hf23  1  0.64  0.44  0.44  1.0
  B  B0  1  0.34  0.02  0.02  1.0
  B  B1  1  0.02  0.34  0.02  1.0
  B  B2  1  0.34  0.34  0.34  1.0
  B  B3  1  0.02  0.02  0.34  1.0
  B  B4  1  0.04  0.04  0.93  1.0
  B  B5  1  0.15  0.04  0.04  1.0
  B  B6  1  0.04  0.15  0.04  1.0
  B  B7  1  0.04  0.93  0.04  1.0
  B  B8  1  0.93  0.04  0.04  1.0
  B  B9  1  0.04  0.04  0.15  1.0
  B  B10  1  0.36  0.36  0.47  1.0
  B  B11  1  0.25  0.36  0.36  1.0
  B  B12  1  0.36  0.25  0.36  1.0
  B  B13  1  0.36  0.47  0.36  1.0
  B  B14  1  0.47  0.36  0.36  1.0
  B  B15  1  0.36  0.36  0.25  1.0

data_HfB2
_symmetry_space_group_name_H-M   R3m
_cell_length_a   7.58
_cell_length_b   7.58
_cell_length_c   18.56
_cell_angle_alpha   90.0
_cell_angle_beta   90.0
_cell_angle_gamma   120.0
_symmetry_Int_Tables_number   160
_chemical_formula_structural   HfB2
_chemical_formula_sum   'Hf24 B48'
_cell_volume   923.03
_cell_formula_units_Z   24
loop_
 _symmetry_equiv_pos_site_id
 _symmetry_equiv_pos_as_xyz
  1  'x, y, z'
  2  '-y, x-y, z'
  3  '-x+y, -x, z'
  4  '-y, -x, z'
  5  '-x+y, y, z'
  6  'x, x-y, z'
  7  'x+1/3, y+2/3, z+2/3'
  8  '-y+1/3, x-y+2/3, z+2/3'
  9  '-x+y+1/3, -x+2/3, z+2/3'
  10  '-y+1/3, -x+2/3, z+2/3'
  11  '-x+y+1/3, y+2/3, z+2/3'
  12  'x+1/3, x-y+2/3, z+2/3'
  13  'x+2/3, y+1/3, z+1/3'
  14  '-y+2/3, x-y+1/3, z+1/3'
  15  '-x+y+2/3, -x+1/3, z+1/3'
  16  '-y+2/3, -x+1/3, z+1/3'
  17  '-x+y+2/3, y+1/3, z+1/3'
  18  'x+2/3, x-y+1/3, z+1/3'
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  9  0.07  0.13  0.5  1.0
  Hf  Hf1  9  0.13  0.07  0.11  1.0
  Hf  Hf2  3  0.0  0.0  0.24  1.0
  Hf  Hf3  3  0.0  0.0  0.36  1.0
  B  B4  9  0.04  0.07  0.61  1.0
  B  B5  9  0.04  0.07  0.93  1.0
  B  B6  9  0.07  0.04  1.0  1.0
  B  B7  9  0.07  0.04  0.68  1.0
  B  B8  9  0.11  0.21  0.87  1.0
  B  B9  3  0.0  0.0  0.66  1.0

Hf Hf Hf Hf Hf Hf Hf Hf B B B B B B B B B B B B B B B B
HfB2 crystallizes in the trigonal R3m space group. There are four inequivalent Hf sites. In the first Hf site, Hf(1) is bonded in a 4-coordinate geometry to one Hf(2), two equivalent Hf(1), one B(1), and one B(3) atom. The Hf(1)-Hf(2) bond length is 2.62 Å. Both Hf(1)-Hf(1) bond lengths are 1.51 Å. The Hf(1)-B(1) bond length is 2.79 Å. The Hf(1)-B(3) bond length is 2.07 Å. In the second Hf site, Hf(2) is bonded in a 7-coordinate geometry to one Hf(4), three equivalent Hf(1), and three equivalent B(1) atoms. The Hf(2)-Hf(4) bond length is 2.26 Å. All Hf(2)-B(1) bond lengths are 3.04 Å. In the third Hf site, Hf(3) is bonded in a 3-coordinate geometry to one Hf(4), two equivalent Hf(3), one B(5), and two equivalent B(1) atoms. The Hf(3)-Hf(4) bond length is 2.62 Å. Both Hf(3)-Hf(3) bond lengths are 1.51 Å. The Hf(3)-B(5) bond length is 2.07 Å. Both Hf(3)-B(1) bond lengths are 3.17 Å. In the fourth Hf site, Hf(4) is bonded in a distorted single-bond geometry to one Hf(2) and three equivalent Hf(3) atoms. There are six inequivalent B sites. In the first B site, B(5) is bonded in a 4-coordinate geometry to one Hf(3), one B(2), and two equivalent B(5) atoms. The B(5)-B(2) bond length is 1.13 Å. Both B(5)-B(5) bond lengths are 0.83 Å. In the second B site, B(6) is bonded in a single-bond geometry to one B(2) atom. The B(6)-B(2) bond length is 0.58 Å. In the third B site, B(1) is bonded in a 5-coordinate geometry to one Hf(1), one Hf(2), two equivalent Hf(3), and one B(4) atom. The B(1)-B(4) bond length is 1.34 Å. In the fourth B site, B(2) is bonded in a 3-coordinate geometry to three equivalent B(5) and three equivalent B(6) atoms. In the fifth B site, B(3) is bonded in a 3-coordinate geometry to one Hf(1) and two equivalent B(3) atoms. Both B(3)-B(3) bond lengths are 0.83 Å. In the sixth B site, B(4) is bonded in a 3-coordinate geometry to one B(1) and two equivalent B(4) atoms. Both B(4)-B(4) bond lengths are 0.83 Å.