The material described by FeNbO4 is Hydrophilite-derived structured and crystallizes in the monoclinic P2 space group. There are three inequivalent Nb sites. In the first Nb site, Nb(1) is bonded to one O(1), one O(2), one O(3), one O(4), one O(6), and one O(8) atom to form NbO6 octahedra that share corners with two equivalent Nb(2)O6 octahedra, corners with two equivalent Fe(1)O6 octahedra, corners with four equivalent Fe(2)O6 octahedra,  an edgeedge with one Nb(3)O6 octahedra, and  an edgeedge with one Fe(3)O6 octahedra. The corner-sharing octahedral tilt angles range from 49-54°. In the second Nb site, Nb(2) is bonded to two equivalent O(3), two equivalent O(7), and two equivalent O(8) atoms to form NbO6 octahedra that share corners with four equivalent Nb(1)O6 octahedra, corners with four equivalent Fe(3)O6 octahedra, and edges with two equivalent Fe(2)O6 octahedra. The corner-sharing octahedral tilt angles range from 49-51°. In the third Nb site, Nb(3) is bonded to two equivalent O(1), two equivalent O(2), and two equivalent O(5) atoms to form distorted NbO6 octahedra that share corners with four equivalent Fe(1)O6 octahedra, corners with four equivalent Fe(2)O6 octahedra, and edges with two equivalent Nb(1)O6 octahedra. The corner-sharing octahedral tilt angles range from 50-53°. There are three inequivalent Fe sites. In the first Fe site, Fe(1) is bonded to two equivalent O(1), two equivalent O(5), and two equivalent O(6) atoms to form FeO6 octahedra that share corners with four equivalent Nb(1)O6 octahedra, corners with four equivalent Nb(3)O6 octahedra, and edges with two equivalent Fe(2)O6 octahedra. The corner-sharing octahedral tilt angles range from 50-54°. In the second Fe site, Fe(2) is bonded to one O(2), one O(4), one O(5), one O(6), one O(7), and one O(8) atom to form distorted FeO6 octahedra that share corners with two equivalent Nb(3)O6 octahedra, corners with two equivalent Fe(3)O6 octahedra, corners with four equivalent Nb(1)O6 octahedra,  an edgeedge with one Nb(2)O6 octahedra, and  an edgeedge with one Fe(1)O6 octahedra. The corner-sharing octahedral tilt angles range from 51-55°. In the third Fe site, Fe(3) is bonded to two equivalent O(3), two equivalent O(4), and two equivalent O(7) atoms to form distorted FeO6 octahedra that share corners with four equivalent Nb(2)O6 octahedra, corners with four equivalent Fe(2)O6 octahedra, and edges with two equivalent Nb(1)O6 octahedra. The corner-sharing octahedral tilt angles range from 51-55°. There are eight inequivalent O sites. In the first O site, O(1) is bonded in a distorted trigonal planar geometry to one Nb(1), one Nb(3), and one Fe(1) atom. In the second O site, O(2) is bonded in a trigonal planar geometry to one Nb(1), one Nb(3), and one Fe(2) atom. In the third O site, O(3) is bonded in a distorted trigonal planar geometry to one Nb(1), one Nb(2), and one Fe(3) atom. In the fourth O site, O(4) is bonded in a trigonal planar geometry to one Nb(1), one Fe(2), and one Fe(3) atom. In the fifth O site, O(5) is bonded in a distorted trigonal planar geometry to one Nb(3), one Fe(1), and one Fe(2) atom. In the sixth O site, O(6) is bonded in a distorted trigonal planar geometry to one Nb(1), one Fe(1), and one Fe(2) atom. In the seventh O site, O(7) is bonded in a trigonal planar geometry to one Nb(2), one Fe(2), and one Fe(3) atom. In the eighth O site, O(8) is bonded in a distorted trigonal planar geometry to one Nb(1), one Nb(2), and one Fe(2) atom. is represented by the Crystallographic Information File (CIF) [CIF]
data_NbFeO4
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.693
_cell_length_b   4.714
_cell_length_c   10.161
_cell_angle_alpha   89.737
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   272.684
_cell_formula_units_Z   4
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
  Nb  Nb0  1  0.831  0.995  0.755  1.0
  Nb  Nb1  1  0.659  0.500  0.500  1.0
  Nb  Nb2  1  0.189  0.000  0.000  1.0
  Nb  Nb3  1  0.831  0.005  0.245  1.0
  Fe  Fe4  1  0.659  0.500  0.000  1.0
  Fe  Fe5  1  0.326  0.498  0.255  1.0
  Fe  Fe6  1  0.326  0.502  0.745  1.0
  Fe  Fe7  1  0.173  0.000  0.500  1.0
  O  O8  1  0.886  0.773  0.915  1.0
  O  O9  1  0.116  0.774  0.162  1.0
  O  O10  1  0.879  0.767  0.414  1.0
  O  O11  1  0.111  0.783  0.668  1.0
  O  O12  1  0.385  0.730  0.916  1.0
  O  O13  1  0.622  0.729  0.166  1.0
  O  O14  1  0.389  0.722  0.416  1.0
  O  O15  1  0.616  0.733  0.666  1.0
  O  O16  1  0.385  0.270  0.084  1.0
  O  O17  1  0.616  0.267  0.334  1.0
  O  O18  1  0.389  0.278  0.584  1.0
  O  O19  1  0.622  0.271  0.834  1.0
  O  O20  1  0.886  0.227  0.085  1.0
  O  O21  1  0.111  0.217  0.332  1.0
  O  O22  1  0.879  0.233  0.586  1.0
  O  O23  1  0.116  0.226  0.838  1.0
[/CIF]
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The material described by FeNbO4 is Hydrophilite-derived structured and crystallizes in the monoclinic P2 space group. There are three inequivalent Nb sites. In the first Nb site, Nb(1) is bonded to one O(1), one O(2), one O(3), one O(4), one O(6), and one O(8) atom to form NbO6 octahedra that share corners with two equivalent Nb(2)O6 octahedra, corners with two equivalent Fe(1)O6 octahedra, corners with four equivalent Fe(2)O6 octahedra,  an edgeedge with one Nb(3)O6 octahedra, and  an edgeedge with one Fe(3)O6 octahedra. The corner-sharing octahedral tilt angles range from 49-54°. In the second Nb site, Nb(2) is bonded to two equivalent O(3), two equivalent O(7), and two equivalent O(8) atoms to form NbO6 octahedra that share corners with four equivalent Nb(1)O6 octahedra, corners with four equivalent Fe(3)O6 octahedra, and edges with two equivalent Fe(2)O6 octahedra. The corner-sharing octahedral tilt angles range from 49-51°. In the third Nb site, Nb(3) is bonded to two equivalent O(1), two equivalent O(2), and two equivalent O(5) atoms to form distorted NbO6 octahedra that share corners with four equivalent Fe(1)O6 octahedra, corners with four equivalent Fe(2)O6 octahedra, and edges with two equivalent Nb(1)O6 octahedra. The corner-sharing octahedral tilt angles range from 50-53°. There are three inequivalent Fe sites. In the first Fe site, Fe(1) is bonded to two equivalent O(1), two equivalent O(5), and two equivalent O(6) atoms to form FeO6 octahedra that share corners with four equivalent Nb(1)O6 octahedra, corners with four equivalent Nb(3)O6 octahedra, and edges with two equivalent Fe(2)O6 octahedra. The corner-sharing octahedral tilt angles range from 50-54°. In the second Fe site, Fe(2) is bonded to one O(2), one O(4), one O(5), one O(6), one O(7), and one O(8) atom to form distorted FeO6 octahedra that share corners with two equivalent Nb(3)O6 octahedra, corners with two equivalent Fe(3)O6 octahedra, corners with four equivalent Nb(1)O6 octahedra,  an edgeedge with one Nb(2)O6 octahedra, and  an edgeedge with one Fe(1)O6 octahedra. The corner-sharing octahedral tilt angles range from 51-55°. In the third Fe site, Fe(3) is bonded to two equivalent O(3), two equivalent O(4), and two equivalent O(7) atoms to form distorted FeO6 octahedra that share corners with four equivalent Nb(2)O6 octahedra, corners with four equivalent Fe(2)O6 octahedra, and edges with two equivalent Nb(1)O6 octahedra. The corner-sharing octahedral tilt angles range from 51-55°. There are eight inequivalent O sites. In the first O site, O(1) is bonded in a distorted trigonal planar geometry to one Nb(1), one Nb(3), and one Fe(1) atom. In the second O site, O(2) is bonded in a trigonal planar geometry to one Nb(1), one Nb(3), and one Fe(2) atom. In the third O site, O(3) is bonded in a distorted trigonal planar geometry to one Nb(1), one Nb(2), and one Fe(3) atom. In the fourth O site, O(4) is bonded in a trigonal planar geometry to one Nb(1), one Fe(2), and one Fe(3) atom. In the fifth O site, O(5) is bonded in a distorted trigonal planar geometry to one Nb(3), one Fe(1), and one Fe(2) atom. In the sixth O site, O(6) is bonded in a distorted trigonal planar geometry to one Nb(1), one Fe(1), and one Fe(2) atom. In the seventh O site, O(7) is bonded in a trigonal planar geometry to one Nb(2), one Fe(2), and one Fe(3) atom. In the eighth O site, O(8) is bonded in a distorted trigonal planar geometry to one Nb(1), one Nb(2), and one Fe(2) atom. is represented by the Crystallographic Information File (CIF) [CIF]
data_NbFeO4
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.693
_cell_length_b   4.714
_cell_length_c   10.161
_cell_angle_alpha   89.737
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   272.684
_cell_formula_units_Z   4
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
  Nb  Nb0  1  0.831  0.995  0.755  1.0
  Nb  Nb1  1  0.659  0.500  0.500  1.0
  Nb  Nb2  1  0.189  0.000  0.000  1.0
  Nb  Nb3  1  0.831  0.005  0.245  1.0
  Fe  Fe4  1  0.659  0.500  0.000  1.0
  Fe  Fe5  1  0.326  0.498  0.255  1.0
  Fe  Fe6  1  0.326  0.502  0.745  1.0
  Fe  Fe7  1  0.173  0.000  0.500  1.0
  O  O8  1  0.886  0.773  0.915  1.0
  O  O9  1  0.116  0.774  0.162  1.0
  O  O10  1  0.879  0.767  0.414  1.0
  O  O11  1  0.111  0.783  0.668  1.0
  O  O12  1  0.385  0.730  0.916  1.0
  O  O13  1  0.622  0.729  0.166  1.0
  O  O14  1  0.389  0.722  0.416  1.0
  O  O15  1  0.616  0.733  0.666  1.0
  O  O16  1  0.385  0.270  0.084  1.0
  O  O17  1  0.616  0.267  0.334  1.0
  O  O18  1  0.389  0.278  0.584  1.0
  O  O19  1  0.622  0.271  0.834  1.0
  O  O20  1  0.886  0.227  0.085  1.0
  O  O21  1  0.111  0.217  0.332  1.0
  O  O22  1  0.879  0.233  0.586  1.0
  O  O23  1  0.116  0.226  0.838  1.0
[/CIF]
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