data_HfGa2As
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   4.89
_cell_length_b   4.89
_cell_length_c   4.89
_cell_angle_alpha   60.0
_cell_angle_beta   60.0
_cell_angle_gamma   60.0
_symmetry_Int_Tables_number   1
_chemical_formula_structural   HfGa2As
_chemical_formula_sum   'Hf1 Ga2 As1'
_cell_volume   82.86
_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  Hf3  1  0.19  0.19  0.19  1.0
  Ga  Ga1  1  0.0  0.0  0.0  1.0
  Ga  Ga2  1  0.73  0.73  0.73  1.0
  As  As0  1  0.46  0.46  0.46  1.0

data_HfGa2As
_symmetry_space_group_name_H-M   R3m
_cell_length_a   4.89
_cell_length_b   4.89
_cell_length_c   11.99
_cell_angle_alpha   90.0
_cell_angle_beta   90.0
_cell_angle_gamma   120.0
_symmetry_Int_Tables_number   160
_chemical_formula_structural   HfGa2As
_chemical_formula_sum   'Hf3 Ga6 As3'
_cell_volume   248.59
_cell_formula_units_Z   3
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  3  0.0  0.0  0.81  1.0
  Ga  Ga1  3  0.0  0.0  0.0  1.0
  Ga  Ga2  3  0.0  0.0  0.27  1.0
  As  As3  3  0.0  0.0  0.54  1.0

Hf Ga Ga As
HfGa2As crystallizes in the trigonal R3m space group. Hf(1) is bonded in a 1-coordinate geometry to one Ga(1) and four equivalent As(1) atoms. The Hf(1)-Ga(1) bond length is 2.28 Å. There are three shorter (2.93 Å) and one longer (3.23 Å) Hf(1)-As(1) bond length. There are two inequivalent Ga sites. In the first Ga site, Ga(1) is bonded in a single-bond geometry to one Hf(1) atom. In the second Ga site, Ga(2) is bonded in a 3-coordinate geometry to three equivalent As(1) atoms. All Ga(2)-As(1) bond lengths are 2.93 Å. As(1) is bonded in a 7-coordinate geometry to four equivalent Hf(1) and three equivalent Ga(2) atoms.