data_HfP2Se
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   7.78
_cell_length_b   7.78
_cell_length_c   7.78
_cell_angle_alpha   25.59
_cell_angle_beta   25.59
_cell_angle_gamma   25.59
_symmetry_Int_Tables_number   1
_chemical_formula_structural   HfP2Se
_chemical_formula_sum   'Hf1 P2 Se1'
_cell_volume   77.2
_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  0.0  0.0  0.7  1.0
  P  P1  1  0.0  0.0  0.17  1.0
  P  P2  1  0.0  0.0  0.45  1.0
  Se  Se3  1  0.0  0.0  0.51  1.0

data_HfP2Se
_symmetry_space_group_name_H-M   Cm
_cell_length_a   5.96
_cell_length_b   3.44
_cell_length_c   7.78
_cell_angle_alpha   90.0
_cell_angle_beta   104.81
_cell_angle_gamma   90.0
_symmetry_Int_Tables_number   8
_chemical_formula_structural   HfP2Se
_chemical_formula_sum   'Hf2 P4 Se2'
_cell_volume   154.4
_cell_formula_units_Z   2
loop_
 _symmetry_equiv_pos_site_id
 _symmetry_equiv_pos_as_xyz
  1  'x, y, z'
  2  'x, -y, z'
  3  'x+1/2, y+1/2, z'
  4  'x+1/2, -y+1/2, 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  2  0.0  0.0  0.3  1.0
  P  P1  2  0.0  0.0  0.55  1.0
  P  P2  2  0.0  0.0  0.83  1.0
  Se  Se3  2  0.0  0.0  0.49  1.0

Hf P P Se
HfP2Se is Cyanogen Chloride-like structured and crystallizes in the monoclinic Cm space group. The structure is zero-dimensional and consists of two HfP2Se clusters. Hf(1) is bonded in a single-bond geometry to one Se(1) atom. The Hf(1)-Se(1) bond length is 1.45 Å. There are two inequivalent P sites. In the first P site, P(1) is bonded in a single-bond geometry to one P(2) atom. The P(1)-P(2) bond length is 2.18 Å. In the second P site, P(2) is bonded in a single-bond geometry to one P(1) and one Se(1) atom. The P(2)-Se(1) bond length is 0.51 Å. Se(1) is bonded in a linear geometry to one Hf(1) and one P(2) atom.