data_HfTeSe2
_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   HfTeSe2
_chemical_formula_sum   'Hf1 Te1 Se2'
_cell_volume   82.55
_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  0.46  0.46  0.46  1.0
  Te  Te3  1  0.0  0.0  0.0  1.0
  Se  Se1  1  0.18  0.18  0.18  1.0
  Se  Se2  1  0.73  0.73  0.73  1.0

data_HfTeSe2
_symmetry_space_group_name_H-M   R3m
_cell_length_a   4.89
_cell_length_b   4.89
_cell_length_c   11.97
_cell_angle_alpha   90.0
_cell_angle_beta   90.0
_cell_angle_gamma   120.0
_symmetry_Int_Tables_number   160
_chemical_formula_structural   HfTeSe2
_chemical_formula_sum   'Hf3 Te3 Se6'
_cell_volume   247.64
_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  0.54  1.0
  Te  Te1  3  0.0  0.0  0.0  1.0
  Se  Se2  3  0.0  0.0  0.27  1.0
  Se  Se3  3  0.0  0.0  0.82  1.0

Hf Te Se Se
HfTeSe2 is Heusler structured and crystallizes in the trigonal R3m space group. Hf(1) is bonded in a 11-coordinate geometry to three equivalent Te(1), four equivalent Se(1), and four equivalent Se(2) atoms. All Hf(1)-Te(1) bond lengths are 3.18 Å. There are three shorter (2.92 Å) and one longer (3.26 Å) Hf(1)-Se(1) bond length. There are three shorter (2.92 Å) and one longer (3.26 Å) Hf(1)-Se(2) bond length. Te(1) is bonded in a distorted single-bond geometry to three equivalent Hf(1), one Se(1), and four equivalent Se(2) atoms. The Te(1)-Se(1) bond length is 2.20 Å. There are three shorter (2.92 Å) and one longer (3.26 Å) Te(1)-Se(2) bond length. There are two inequivalent Se sites. In the first Se site, Se(1) is bonded in a 5-coordinate geometry to four equivalent Hf(1) and one Te(1) atom. In the second Se site, Se(2) is bonded in a 8-coordinate geometry to four equivalent Hf(1) and four equivalent Te(1) atoms.