The compound described by Hf3N4 crystallizes in the trigonal R-3m space group. There are two inequivalent Hf sites. In the first Hf site, Hf(1) is bonded in a 7-coordinate geometry to three equivalent N(1) and four equivalent N(2) atoms. In the second Hf site, Hf(2) is bonded to six equivalent N(1) atoms to form edge-sharing HfN6 octahedra. There are two inequivalent N sites. In the first N site, N(1) is bonded to three equivalent Hf(1) and three equivalent Hf(2) atoms to form NHf6 octahedra that share corners with three equivalent N(1)Hf6 octahedra, corners with six equivalent N(2)Hf4 tetrahedra, edges with nine equivalent N(1)Hf6 octahedra, and edges with three equivalent N(2)Hf4 tetrahedra. The corner-sharing octahedra are not tilted. In the second N site, N(2) is bonded to four equivalent Hf(1) atoms to form NHf4 tetrahedra that share corners with six equivalent N(1)Hf6 octahedra, corners with six equivalent N(2)Hf4 tetrahedra, edges with three equivalent N(1)Hf6 octahedra, and edges with three equivalent N(2)Hf4 tetrahedra. The corner-sharing octahedral tilt angles range from 25-50°. is represented by the Crystallographic Information File (CIF) [CIF]
data_Hf3N4
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   8.639
_cell_length_b   8.639
_cell_length_c   8.639
_cell_angle_alpha   22.760
_cell_angle_beta   22.760
_cell_angle_gamma   22.760
_symmetry_Int_Tables_number   1
_cell_volume   84.666
_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  0.222  0.222  0.222  1.0
  Hf  Hf1  1  0.778  0.778  0.778  1.0
  Hf  Hf2  1  0.000  0.000  0.000  1.0
  N  N3  1  0.622  0.622  0.622  1.0
  N  N4  1  0.868  0.868  0.868  1.0
  N  N5  1  0.132  0.132  0.132  1.0
  N  N6  1  0.378  0.378  0.378  1.0
[/CIF]
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The compound described by Hf3N4 crystallizes in the trigonal R-3m space group. There are two inequivalent Hf sites. In the first Hf site, Hf(1) is bonded in a 7-coordinate geometry to three equivalent N(1) and four equivalent N(2) atoms. In the second Hf site, Hf(2) is bonded to six equivalent N(1) atoms to form edge-sharing HfN6 octahedra. There are two inequivalent N sites. In the first N site, N(1) is bonded to three equivalent Hf(1) and three equivalent Hf(2) atoms to form NHf6 octahedra that share corners with three equivalent N(1)Hf6 octahedra, corners with six equivalent N(2)Hf4 tetrahedra, edges with nine equivalent N(1)Hf6 octahedra, and edges with three equivalent N(2)Hf4 tetrahedra. The corner-sharing octahedra are not tilted. In the second N site, N(2) is bonded to four equivalent Hf(1) atoms to form NHf4 tetrahedra that share corners with six equivalent N(1)Hf6 octahedra, corners with six equivalent N(2)Hf4 tetrahedra, edges with three equivalent N(1)Hf6 octahedra, and edges with three equivalent N(2)Hf4 tetrahedra. The corner-sharing octahedral tilt angles range from 25-50°. is represented by the Crystallographic Information File (CIF) [CIF]
data_Hf3N4
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   8.639
_cell_length_b   8.639
_cell_length_c   8.639
_cell_angle_alpha   22.760
_cell_angle_beta   22.760
_cell_angle_gamma   22.760
_symmetry_Int_Tables_number   1
_cell_volume   84.666
_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  0.222  0.222  0.222  1.0
  Hf  Hf1  1  0.778  0.778  0.778  1.0
  Hf  Hf2  1  0.000  0.000  0.000  1.0
  N  N3  1  0.622  0.622  0.622  1.0
  N  N4  1  0.868  0.868  0.868  1.0
  N  N5  1  0.132  0.132  0.132  1.0
  N  N6  1  0.378  0.378  0.378  1.0
[/CIF]
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