The structure described by HfNb4CN4 is alpha Po-derived structured and crystallizes in the tetragonal I4/mmm space group. Hf(1) is bonded to four equivalent C(1) and two equivalent N(1) atoms to form HfC4N2 octahedra that share corners with two equivalent Nb(2)N6 octahedra, corners with four equivalent Hf(1)C4N2 octahedra, edges with four equivalent Hf(1)C4N2 octahedra, and edges with eight equivalent Nb(1)CN5 octahedra. The corner-sharing octahedra are not tilted. There are two inequivalent Nb sites. In the first Nb site, Nb(1) is bonded to one C(1), one N(2), and four equivalent N(1) atoms to form NbCN5 octahedra that share  a cornercorner with one Nb(2)N6 octahedra, corners with five equivalent Nb(1)CN5 octahedra, edges with four equivalent Hf(1)C4N2 octahedra, edges with four equivalent Nb(1)CN5 octahedra, and edges with four equivalent Nb(2)N6 octahedra. The corner-sharing octahedral tilt angles range from 0-1°. In the second Nb site, Nb(2) is bonded to one N(1) and five equivalent N(2) atoms to form NbN6 octahedra that share  a cornercorner with one Hf(1)C4N2 octahedra,  a cornercorner with one Nb(1)CN5 octahedra, corners with four equivalent Nb(2)N6 octahedra, edges with four equivalent Nb(1)CN5 octahedra, and edges with eight equivalent Nb(2)N6 octahedra. The corner-sharing octahedra are not tilted. C(1) is bonded to four equivalent Hf(1) and two equivalent Nb(1) atoms to form CHf4Nb2 octahedra that share corners with two equivalent N(2)Nb6 octahedra, corners with four equivalent C(1)Hf4Nb2 octahedra, edges with four equivalent C(1)Hf4Nb2 octahedra, and edges with eight equivalent N(1)HfNb5 octahedra. The corner-sharing octahedra are not tilted. There are two inequivalent N sites. In the first N site, N(1) is bonded to one Hf(1), one Nb(2), and four equivalent Nb(1) atoms to form NHfNb5 octahedra that share  a cornercorner with one N(2)Nb6 octahedra, corners with five equivalent N(1)HfNb5 octahedra, edges with four equivalent C(1)Hf4Nb2 octahedra, edges with four equivalent N(1)HfNb5 octahedra, and edges with four equivalent N(2)Nb6 octahedra. The corner-sharing octahedral tilt angles range from 0-1°. In the second N site, N(2) is bonded to one Nb(1) and five equivalent Nb(2) atoms to form NNb6 octahedra that share  a cornercorner with one C(1)Hf4Nb2 octahedra,  a cornercorner with one N(1)HfNb5 octahedra, corners with four equivalent N(2)Nb6 octahedra, edges with four equivalent N(1)HfNb5 octahedra, and edges with eight equivalent N(2)Nb6 octahedra. The corner-sharing octahedra are not tilted. is represented by the Crystallographic Information File (CIF) [CIF]
data_HfNb4CN4
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   11.380
_cell_length_b   11.380
_cell_length_c   11.380
_cell_angle_alpha   163.961
_cell_angle_beta   163.961
_cell_angle_gamma   22.758
_symmetry_Int_Tables_number   1
_cell_volume   112.495
_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  0.000  0.000  0.000  1.0
  Nb  Nb1  1  0.401  0.401  0.000  1.0
  Nb  Nb2  1  0.800  0.800  0.000  1.0
  Nb  Nb3  1  0.200  0.200  0.000  1.0
  Nb  Nb4  1  0.599  0.599  0.000  1.0
  C  C5  1  0.500  0.500  0.000  1.0
  N  N6  1  0.900  0.900  0.000  1.0
  N  N7  1  0.300  0.300  0.000  1.0
  N  N8  1  0.700  0.700  0.000  1.0
  N  N9  1  0.100  0.100  0.000  1.0
[/CIF]
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The structure described by HfNb4CN4 is alpha Po-derived structured and crystallizes in the tetragonal I4/mmm space group. Hf(1) is bonded to four equivalent C(1) and two equivalent N(1) atoms to form HfC4N2 octahedra that share corners with two equivalent Nb(2)N6 octahedra, corners with four equivalent Hf(1)C4N2 octahedra, edges with four equivalent Hf(1)C4N2 octahedra, and edges with eight equivalent Nb(1)CN5 octahedra. The corner-sharing octahedra are not tilted. There are two inequivalent Nb sites. In the first Nb site, Nb(1) is bonded to one C(1), one N(2), and four equivalent N(1) atoms to form NbCN5 octahedra that share  a cornercorner with one Nb(2)N6 octahedra, corners with five equivalent Nb(1)CN5 octahedra, edges with four equivalent Hf(1)C4N2 octahedra, edges with four equivalent Nb(1)CN5 octahedra, and edges with four equivalent Nb(2)N6 octahedra. The corner-sharing octahedral tilt angles range from 0-1°. In the second Nb site, Nb(2) is bonded to one N(1) and five equivalent N(2) atoms to form NbN6 octahedra that share  a cornercorner with one Hf(1)C4N2 octahedra,  a cornercorner with one Nb(1)CN5 octahedra, corners with four equivalent Nb(2)N6 octahedra, edges with four equivalent Nb(1)CN5 octahedra, and edges with eight equivalent Nb(2)N6 octahedra. The corner-sharing octahedra are not tilted. C(1) is bonded to four equivalent Hf(1) and two equivalent Nb(1) atoms to form CHf4Nb2 octahedra that share corners with two equivalent N(2)Nb6 octahedra, corners with four equivalent C(1)Hf4Nb2 octahedra, edges with four equivalent C(1)Hf4Nb2 octahedra, and edges with eight equivalent N(1)HfNb5 octahedra. The corner-sharing octahedra are not tilted. There are two inequivalent N sites. In the first N site, N(1) is bonded to one Hf(1), one Nb(2), and four equivalent Nb(1) atoms to form NHfNb5 octahedra that share  a cornercorner with one N(2)Nb6 octahedra, corners with five equivalent N(1)HfNb5 octahedra, edges with four equivalent C(1)Hf4Nb2 octahedra, edges with four equivalent N(1)HfNb5 octahedra, and edges with four equivalent N(2)Nb6 octahedra. The corner-sharing octahedral tilt angles range from 0-1°. In the second N site, N(2) is bonded to one Nb(1) and five equivalent Nb(2) atoms to form NNb6 octahedra that share  a cornercorner with one C(1)Hf4Nb2 octahedra,  a cornercorner with one N(1)HfNb5 octahedra, corners with four equivalent N(2)Nb6 octahedra, edges with four equivalent N(1)HfNb5 octahedra, and edges with eight equivalent N(2)Nb6 octahedra. The corner-sharing octahedra are not tilted. is represented by the Crystallographic Information File (CIF) [CIF]
data_HfNb4CN4
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   11.380
_cell_length_b   11.380
_cell_length_c   11.380
_cell_angle_alpha   163.961
_cell_angle_beta   163.961
_cell_angle_gamma   22.758
_symmetry_Int_Tables_number   1
_cell_volume   112.495
_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  0.000  0.000  0.000  1.0
  Nb  Nb1  1  0.401  0.401  0.000  1.0
  Nb  Nb2  1  0.800  0.800  0.000  1.0
  Nb  Nb3  1  0.200  0.200  0.000  1.0
  Nb  Nb4  1  0.599  0.599  0.000  1.0
  C  C5  1  0.500  0.500  0.000  1.0
  N  N6  1  0.900  0.900  0.000  1.0
  N  N7  1  0.300  0.300  0.000  1.0
  N  N8  1  0.700  0.700  0.000  1.0
  N  N9  1  0.100  0.100  0.000  1.0
[/CIF]
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