The compound described by Hf3N2O3 crystallizes in the orthorhombic Cmc2_1 space group. There are three inequivalent Hf sites. In the first Hf site, Hf(1) is bonded to one N(1), one N(2), one O(1), one O(3), and two equivalent O(2) atoms to form a mixture of distorted corner and edge-sharing HfN2O4 octahedra. The corner-sharing octahedral tilt angles range from 28-35°. In the second Hf site, Hf(2) is bonded in a 6-coordinate geometry to one N(1), two equivalent N(2), one O(1), one O(2), and one O(3) atom. In the third Hf site, Hf(3) is bonded to one N(1), one N(2), one O(1), one O(2), and two equivalent O(3) atoms to form a mixture of distorted corner and edge-sharing HfN2O4 octahedra. The corner-sharing octahedral tilt angles range from 28-41°. There are two inequivalent N sites. In the first N site, N(1) is bonded in a distorted T-shaped geometry to one Hf(1), one Hf(2), and one Hf(3) atom. In the second N site, N(2) is bonded to one Hf(1), one Hf(3), and two equivalent Hf(2) atoms to form NHf4 tetrahedra that share  a cornercorner with one O(3)Hf4 tetrahedra, corners with two equivalent N(2)Hf4 tetrahedra,  a cornercorner with one O(2)Hf4 trigonal pyramid, edges with two equivalent O(3)Hf4 tetrahedra, and edges with two equivalent O(2)Hf4 trigonal pyramids. There are three inequivalent O sites. In the first O site, O(1) is bonded in a distorted T-shaped geometry to one Hf(1), one Hf(2), and one Hf(3) atom. In the second O site, O(2) is bonded to one Hf(2), one Hf(3), and two equivalent Hf(1) atoms to form OHf4 trigonal pyramids that share  a cornercorner with one N(2)Hf4 tetrahedra,  a cornercorner with one O(3)Hf4 tetrahedra, corners with two equivalent O(2)Hf4 trigonal pyramids, edges with two equivalent N(2)Hf4 tetrahedra, and edges with two equivalent O(3)Hf4 tetrahedra. In the third O site, O(3) is bonded to one Hf(1), one Hf(2), and two equivalent Hf(3) atoms to form distorted OHf4 tetrahedra that share  a cornercorner with one N(2)Hf4 tetrahedra, corners with two equivalent O(3)Hf4 tetrahedra,  a cornercorner with one O(2)Hf4 trigonal pyramid, edges with two equivalent N(2)Hf4 tetrahedra, and edges with two equivalent O(2)Hf4 trigonal pyramids. is represented by the CIF file [CIF]
data_Hf3N2O3
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.680
_cell_length_b   5.680
_cell_length_c   10.736
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   139.210
_symmetry_Int_Tables_number   1
_cell_volume   226.265
_cell_formula_units_Z   2
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  0.137  0.863  0.940  1.0
  Hf  Hf1  1  0.135  0.865  0.553  1.0
  Hf  Hf2  1  0.186  0.814  0.249  1.0
  Hf  Hf3  1  0.814  0.186  0.749  1.0
  Hf  Hf4  1  0.865  0.135  0.053  1.0
  Hf  Hf5  1  0.863  0.137  0.440  1.0
  N  N6  1  0.047  0.953  0.385  1.0
  N  N7  1  0.705  0.295  0.576  1.0
  N  N8  1  0.295  0.705  0.076  1.0
  N  N9  1  0.953  0.047  0.885  1.0
  O  O10  1  0.045  0.955  0.117  1.0
  O  O11  1  0.692  0.308  0.919  1.0
  O  O12  1  0.755  0.245  0.261  1.0
  O  O13  1  0.245  0.755  0.761  1.0
  O  O14  1  0.308  0.692  0.419  1.0
  O  O15  1  0.955  0.045  0.617  1.0
[/CIF]
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The compound described by Hf3N2O3 crystallizes in the orthorhombic Cmc2_1 space group. There are three inequivalent Hf sites. In the first Hf site, Hf(1) is bonded to one N(1), one N(2), one O(1), one O(3), and two equivalent O(2) atoms to form a mixture of distorted corner and edge-sharing HfN2O4 octahedra. The corner-sharing octahedral tilt angles range from 28-35°. In the second Hf site, Hf(2) is bonded in a 6-coordinate geometry to one N(1), two equivalent N(2), one O(1), one O(2), and one O(3) atom. In the third Hf site, Hf(3) is bonded to one N(1), one N(2), one O(1), one O(2), and two equivalent O(3) atoms to form a mixture of distorted corner and edge-sharing HfN2O4 octahedra. The corner-sharing octahedral tilt angles range from 28-41°. There are two inequivalent N sites. In the first N site, N(1) is bonded in a distorted T-shaped geometry to one Hf(1), one Hf(2), and one Hf(3) atom. In the second N site, N(2) is bonded to one Hf(1), one Hf(3), and two equivalent Hf(2) atoms to form NHf4 tetrahedra that share  a cornercorner with one O(3)Hf4 tetrahedra, corners with two equivalent N(2)Hf4 tetrahedra,  a cornercorner with one O(2)Hf4 trigonal pyramid, edges with two equivalent O(3)Hf4 tetrahedra, and edges with two equivalent O(2)Hf4 trigonal pyramids. There are three inequivalent O sites. In the first O site, O(1) is bonded in a distorted T-shaped geometry to one Hf(1), one Hf(2), and one Hf(3) atom. In the second O site, O(2) is bonded to one Hf(2), one Hf(3), and two equivalent Hf(1) atoms to form OHf4 trigonal pyramids that share  a cornercorner with one N(2)Hf4 tetrahedra,  a cornercorner with one O(3)Hf4 tetrahedra, corners with two equivalent O(2)Hf4 trigonal pyramids, edges with two equivalent N(2)Hf4 tetrahedra, and edges with two equivalent O(3)Hf4 tetrahedra. In the third O site, O(3) is bonded to one Hf(1), one Hf(2), and two equivalent Hf(3) atoms to form distorted OHf4 tetrahedra that share  a cornercorner with one N(2)Hf4 tetrahedra, corners with two equivalent O(3)Hf4 tetrahedra,  a cornercorner with one O(2)Hf4 trigonal pyramid, edges with two equivalent N(2)Hf4 tetrahedra, and edges with two equivalent O(2)Hf4 trigonal pyramids. is represented by the CIF file [CIF]
data_Hf3N2O3
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.680
_cell_length_b   5.680
_cell_length_c   10.736
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   139.210
_symmetry_Int_Tables_number   1
_cell_volume   226.265
_cell_formula_units_Z   2
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  0.137  0.863  0.940  1.0
  Hf  Hf1  1  0.135  0.865  0.553  1.0
  Hf  Hf2  1  0.186  0.814  0.249  1.0
  Hf  Hf3  1  0.814  0.186  0.749  1.0
  Hf  Hf4  1  0.865  0.135  0.053  1.0
  Hf  Hf5  1  0.863  0.137  0.440  1.0
  N  N6  1  0.047  0.953  0.385  1.0
  N  N7  1  0.705  0.295  0.576  1.0
  N  N8  1  0.295  0.705  0.076  1.0
  N  N9  1  0.953  0.047  0.885  1.0
  O  O10  1  0.045  0.955  0.117  1.0
  O  O11  1  0.692  0.308  0.919  1.0
  O  O12  1  0.755  0.245  0.261  1.0
  O  O13  1  0.245  0.755  0.761  1.0
  O  O14  1  0.308  0.692  0.419  1.0
  O  O15  1  0.955  0.045  0.617  1.0
[/CIF]
.