The crystal structure described by HfAs is Molybdenum Carbide MAX Phase-like structured and crystallizes in the hexagonal P6_3/mmc space group. Hf(1) is bonded to three equivalent As(1) and three equivalent As(2) atoms to form a mixture of edge, corner, and face-sharing HfAs6 octahedra. The corner-sharing octahedral tilt angles range from 0-47°. There are two inequivalent As sites. In the first As site, As(1) is bonded to six equivalent Hf(1) atoms to form a mixture of distorted edge and corner-sharing AsHf6 pentagonal pyramids. The corner-sharing octahedral tilt angles are 4°. In the second As site, As(2) is bonded to six equivalent Hf(1) atoms to form a mixture of edge and corner-sharing AsHf6 octahedra. is represented by the Crystallographic Information File (CIF) [CIF]
data_HfAs
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   3.787
_cell_length_b   3.787
_cell_length_c   12.682
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   120.000
_symmetry_Int_Tables_number   1
_cell_volume   157.489
_cell_formula_units_Z   4
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  0.333  0.667  0.383  1.0
  Hf  Hf1  1  0.667  0.333  0.883  1.0
  Hf  Hf2  1  0.667  0.333  0.617  1.0
  Hf  Hf3  1  0.333  0.667  0.117  1.0
  As  As4  1  0.667  0.333  0.250  1.0
  As  As5  1  0.333  0.667  0.750  1.0
  As  As6  1  0.000  0.000  0.500  1.0
  As  As7  1  0.000  0.000  0.000  1.0
[/CIF]
.
The crystal structure described by HfAs is Molybdenum Carbide MAX Phase-like structured and crystallizes in the hexagonal P6_3/mmc space group. Hf(1) is bonded to three equivalent As(1) and three equivalent As(2) atoms to form a mixture of edge, corner, and face-sharing HfAs6 octahedra. The corner-sharing octahedral tilt angles range from 0-47°. There are two inequivalent As sites. In the first As site, As(1) is bonded to six equivalent Hf(1) atoms to form a mixture of distorted edge and corner-sharing AsHf6 pentagonal pyramids. The corner-sharing octahedral tilt angles are 4°. In the second As site, As(2) is bonded to six equivalent Hf(1) atoms to form a mixture of edge and corner-sharing AsHf6 octahedra. is represented by the Crystallographic Information File (CIF) [CIF]
data_HfAs
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   3.787
_cell_length_b   3.787
_cell_length_c   12.682
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   120.000
_symmetry_Int_Tables_number   1
_cell_volume   157.489
_cell_formula_units_Z   4
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  0.333  0.667  0.383  1.0
  Hf  Hf1  1  0.667  0.333  0.883  1.0
  Hf  Hf2  1  0.667  0.333  0.617  1.0
  Hf  Hf3  1  0.333  0.667  0.117  1.0
  As  As4  1  0.667  0.333  0.250  1.0
  As  As5  1  0.333  0.667  0.750  1.0
  As  As6  1  0.000  0.000  0.500  1.0
  As  As7  1  0.000  0.000  0.000  1.0
[/CIF]
.