The material described by Nd3NbO7 crystallizes in the orthorhombic Pnma space group. There are two inequivalent Nd sites. In the first Nd site, Nd(1) is bonded in a 6-coordinate geometry to two equivalent O(1) and four equivalent O(3) atoms. In the second Nd site, Nd(2) is bonded to one O(2), two equivalent O(1), two equivalent O(3), and two equivalent O(4) atoms to form distorted NdO7 pentagonal bipyramids that share corners with two equivalent Nb(1)O6 octahedra, corners with three equivalent Nd(2)O7 pentagonal bipyramids, edges with two equivalent Nb(1)O6 octahedra, and edges with two equivalent Nd(2)O7 pentagonal bipyramids. The corner-sharing octahedral tilt angles range from 30-42°. Nb(1) is bonded to two equivalent O(1), two equivalent O(2), and two equivalent O(4) atoms to form NbO6 octahedra that share corners with two equivalent Nb(1)O6 octahedra, corners with four equivalent Nd(2)O7 pentagonal bipyramids, and edges with four equivalent Nd(2)O7 pentagonal bipyramids. The corner-sharing octahedral tilt angles are 37°. There are four inequivalent O sites. In the first O site, O(1) is bonded to one Nd(1), two equivalent Nd(2), and one Nb(1) atom to form distorted ONd3Nb tetrahedra that share corners with four equivalent O(3)Nd4 tetrahedra, edges with two equivalent O(1)Nd3Nb tetrahedra, and edges with two equivalent O(3)Nd4 tetrahedra. In the second O site, O(2) is bonded in a 4-coordinate geometry to two equivalent Nd(2) and two equivalent Nb(1) atoms. In the third O site, O(3) is bonded to two equivalent Nd(1) and two equivalent Nd(2) atoms to form ONd4 tetrahedra that share corners with four equivalent O(1)Nd3Nb tetrahedra, corners with six equivalent O(3)Nd4 tetrahedra,  an edgeedge with one O(3)Nd4 tetrahedra, and edges with two equivalent O(1)Nd3Nb tetrahedra. In the fourth O site, O(4) is bonded in a 3-coordinate geometry to two equivalent Nd(2) and one Nb(1) atom. is represented by the CIF card [CIF]
data_Nd3NbO7
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   7.634
_cell_length_b   7.683
_cell_length_c   10.956
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   642.602
_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
  Nd  Nd0  1  0.487  0.291  0.250  1.0
  Nd  Nd1  1  0.749  0.545  0.476  1.0
  Nd  Nd2  1  0.251  0.455  0.524  1.0
  Nd  Nd3  1  0.987  0.209  0.250  1.0
  Nd  Nd4  1  0.751  0.045  0.976  1.0
  Nd  Nd5  1  0.751  0.045  0.524  1.0
  Nd  Nd6  1  0.513  0.709  0.750  1.0
  Nd  Nd7  1  0.251  0.455  0.976  1.0
  Nd  Nd8  1  0.013  0.791  0.750  1.0
  Nd  Nd9  1  0.249  0.955  0.024  1.0
  Nd  Nd10  1  0.749  0.545  0.024  1.0
  Nd  Nd11  1  0.249  0.955  0.476  1.0
  Nb  Nb12  1  0.496  0.752  0.250  1.0
  Nb  Nb13  1  0.996  0.748  0.250  1.0
  Nb  Nb14  1  0.004  0.252  0.750  1.0
  Nb  Nb15  1  0.504  0.248  0.750  1.0
  O  O16  1  0.037  0.050  0.627  1.0
  O  O17  1  0.963  0.950  0.127  1.0
  O  O18  1  0.753  0.667  0.250  1.0
  O  O19  1  0.537  0.450  0.627  1.0
  O  O20  1  0.963  0.950  0.373  1.0
  O  O21  1  0.257  0.728  0.618  1.0
  O  O22  1  0.253  0.833  0.250  1.0
  O  O23  1  0.463  0.550  0.373  1.0
  O  O24  1  0.243  0.228  0.382  1.0
  O  O25  1  0.456  0.093  0.613  1.0
  O  O26  1  0.743  0.272  0.118  1.0
  O  O27  1  0.456  0.093  0.887  1.0
  O  O28  1  0.743  0.272  0.382  1.0
  O  O29  1  0.956  0.407  0.887  1.0
  O  O30  1  0.247  0.333  0.750  1.0
  O  O31  1  0.544  0.907  0.387  1.0
  O  O32  1  0.044  0.593  0.113  1.0
  O  O33  1  0.956  0.407  0.613  1.0
  O  O34  1  0.243  0.228  0.118  1.0
  O  O35  1  0.544  0.907  0.113  1.0
  O  O36  1  0.747  0.167  0.750  1.0
  O  O37  1  0.463  0.550  0.127  1.0
  O  O38  1  0.757  0.772  0.882  1.0
  O  O39  1  0.257  0.728  0.882  1.0
  O  O40  1  0.537  0.450  0.873  1.0
  O  O41  1  0.044  0.593  0.387  1.0
  O  O42  1  0.757  0.772  0.618  1.0
  O  O43  1  0.037  0.050  0.873  1.0
[/CIF]
.
The material described by Nd3NbO7 crystallizes in the orthorhombic Pnma space group. There are two inequivalent Nd sites. In the first Nd site, Nd(1) is bonded in a 6-coordinate geometry to two equivalent O(1) and four equivalent O(3) atoms. In the second Nd site, Nd(2) is bonded to one O(2), two equivalent O(1), two equivalent O(3), and two equivalent O(4) atoms to form distorted NdO7 pentagonal bipyramids that share corners with two equivalent Nb(1)O6 octahedra, corners with three equivalent Nd(2)O7 pentagonal bipyramids, edges with two equivalent Nb(1)O6 octahedra, and edges with two equivalent Nd(2)O7 pentagonal bipyramids. The corner-sharing octahedral tilt angles range from 30-42°. Nb(1) is bonded to two equivalent O(1), two equivalent O(2), and two equivalent O(4) atoms to form NbO6 octahedra that share corners with two equivalent Nb(1)O6 octahedra, corners with four equivalent Nd(2)O7 pentagonal bipyramids, and edges with four equivalent Nd(2)O7 pentagonal bipyramids. The corner-sharing octahedral tilt angles are 37°. There are four inequivalent O sites. In the first O site, O(1) is bonded to one Nd(1), two equivalent Nd(2), and one Nb(1) atom to form distorted ONd3Nb tetrahedra that share corners with four equivalent O(3)Nd4 tetrahedra, edges with two equivalent O(1)Nd3Nb tetrahedra, and edges with two equivalent O(3)Nd4 tetrahedra. In the second O site, O(2) is bonded in a 4-coordinate geometry to two equivalent Nd(2) and two equivalent Nb(1) atoms. In the third O site, O(3) is bonded to two equivalent Nd(1) and two equivalent Nd(2) atoms to form ONd4 tetrahedra that share corners with four equivalent O(1)Nd3Nb tetrahedra, corners with six equivalent O(3)Nd4 tetrahedra,  an edgeedge with one O(3)Nd4 tetrahedra, and edges with two equivalent O(1)Nd3Nb tetrahedra. In the fourth O site, O(4) is bonded in a 3-coordinate geometry to two equivalent Nd(2) and one Nb(1) atom. is represented by the CIF card [CIF]
data_Nd3NbO7
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   7.634
_cell_length_b   7.683
_cell_length_c   10.956
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   642.602
_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
  Nd  Nd0  1  0.487  0.291  0.250  1.0
  Nd  Nd1  1  0.749  0.545  0.476  1.0
  Nd  Nd2  1  0.251  0.455  0.524  1.0
  Nd  Nd3  1  0.987  0.209  0.250  1.0
  Nd  Nd4  1  0.751  0.045  0.976  1.0
  Nd  Nd5  1  0.751  0.045  0.524  1.0
  Nd  Nd6  1  0.513  0.709  0.750  1.0
  Nd  Nd7  1  0.251  0.455  0.976  1.0
  Nd  Nd8  1  0.013  0.791  0.750  1.0
  Nd  Nd9  1  0.249  0.955  0.024  1.0
  Nd  Nd10  1  0.749  0.545  0.024  1.0
  Nd  Nd11  1  0.249  0.955  0.476  1.0
  Nb  Nb12  1  0.496  0.752  0.250  1.0
  Nb  Nb13  1  0.996  0.748  0.250  1.0
  Nb  Nb14  1  0.004  0.252  0.750  1.0
  Nb  Nb15  1  0.504  0.248  0.750  1.0
  O  O16  1  0.037  0.050  0.627  1.0
  O  O17  1  0.963  0.950  0.127  1.0
  O  O18  1  0.753  0.667  0.250  1.0
  O  O19  1  0.537  0.450  0.627  1.0
  O  O20  1  0.963  0.950  0.373  1.0
  O  O21  1  0.257  0.728  0.618  1.0
  O  O22  1  0.253  0.833  0.250  1.0
  O  O23  1  0.463  0.550  0.373  1.0
  O  O24  1  0.243  0.228  0.382  1.0
  O  O25  1  0.456  0.093  0.613  1.0
  O  O26  1  0.743  0.272  0.118  1.0
  O  O27  1  0.456  0.093  0.887  1.0
  O  O28  1  0.743  0.272  0.382  1.0
  O  O29  1  0.956  0.407  0.887  1.0
  O  O30  1  0.247  0.333  0.750  1.0
  O  O31  1  0.544  0.907  0.387  1.0
  O  O32  1  0.044  0.593  0.113  1.0
  O  O33  1  0.956  0.407  0.613  1.0
  O  O34  1  0.243  0.228  0.118  1.0
  O  O35  1  0.544  0.907  0.113  1.0
  O  O36  1  0.747  0.167  0.750  1.0
  O  O37  1  0.463  0.550  0.127  1.0
  O  O38  1  0.757  0.772  0.882  1.0
  O  O39  1  0.257  0.728  0.882  1.0
  O  O40  1  0.537  0.450  0.873  1.0
  O  O41  1  0.044  0.593  0.387  1.0
  O  O42  1  0.757  0.772  0.618  1.0
  O  O43  1  0.037  0.050  0.873  1.0
[/CIF]
.