The structure described by KNd2NbO6 crystallizes in the monoclinic C2/m space group. K(1) is bonded in a 7-coordinate geometry to three equivalent O(4) and four equivalent O(2) atoms. There are two inequivalent Nd sites. In the first Nd site, Nd(1) is bonded in a body-centered cubic geometry to two equivalent O(2), two equivalent O(3), and four equivalent O(1) atoms. In the second Nd site, Nd(2) is bonded to one O(4), two equivalent O(1), two equivalent O(2), and two equivalent O(3) atoms to form distorted NdO7 hexagonal pyramids that share corners with three equivalent Nb(1)O5 trigonal bipyramids,  an edgeedge with one Nd(2)O7 hexagonal pyramid, and  an edgeedge with one Nb(1)O5 trigonal bipyramid. Nb(1) is bonded to one O(4), two equivalent O(1), and two equivalent O(2) atoms to form distorted NbO5 trigonal bipyramids that share corners with three equivalent Nd(2)O7 hexagonal pyramids and  an edgeedge with one Nd(2)O7 hexagonal pyramid. There are four inequivalent O sites. In the first O site, O(1) is bonded to one Nd(2), two equivalent Nd(1), and one Nb(1) atom to form distorted ONd3Nb tetrahedra that share corners with two equivalent O(1)Nd3Nb tetrahedra, corners with four equivalent O(3)Nd4 tetrahedra,  an edgeedge with one O(3)Nd4 tetrahedra, and edges with three equivalent O(1)Nd3Nb tetrahedra. In the second O site, O(2) is bonded in a 5-coordinate geometry to two equivalent K(1), one Nd(1), one Nd(2), and one Nb(1) atom. 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 eight equivalent O(1)Nd3Nb tetrahedra, edges with two equivalent O(1)Nd3Nb tetrahedra, and edges with two equivalent O(3)Nd4 tetrahedra. In the fourth O site, O(4) is bonded in a 5-coordinate geometry to three equivalent K(1), one Nd(2), and one Nb(1) atom. is represented by the CIF file [CIF]
data_KNd2NbO6
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   6.967
_cell_length_b   6.967
_cell_length_c   8.842
_cell_angle_alpha   75.589
_cell_angle_beta   75.589
_cell_angle_gamma   48.853
_symmetry_Int_Tables_number   1
_cell_volume   310.874
_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
  K  K0  1  0.884  0.884  0.479  1.0
  K  K1  1  0.116  0.116  0.521  1.0
  Nd  Nd2  1  0.871  0.871  0.930  1.0
  Nd  Nd3  1  0.412  0.412  0.202  1.0
  Nd  Nd4  1  0.588  0.588  0.798  1.0
  Nd  Nd5  1  0.129  0.129  0.070  1.0
  Nb  Nb6  1  0.341  0.341  0.703  1.0
  Nb  Nb7  1  0.659  0.659  0.297  1.0
  O  O8  1  0.469  0.000  0.833  1.0
  O  O9  1  0.314  0.781  0.291  1.0
  O  O10  1  0.251  0.749  0.000  1.0
  O  O11  1  0.686  0.219  0.709  1.0
  O  O12  1  0.781  0.314  0.291  1.0
  O  O13  1  0.749  0.251  0.000  1.0
  O  O14  1  0.219  0.686  0.709  1.0
  O  O15  1  0.531  1.000  0.167  1.0
  O  O16  1  0.326  0.326  0.499  1.0
  O  O17  1  0.674  0.674  0.501  1.0
  O  O18  1  1.000  0.531  0.167  1.0
  O  O19  1  0.000  0.469  0.833  1.0
[/CIF]
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The structure described by KNd2NbO6 crystallizes in the monoclinic C2/m space group. K(1) is bonded in a 7-coordinate geometry to three equivalent O(4) and four equivalent O(2) atoms. There are two inequivalent Nd sites. In the first Nd site, Nd(1) is bonded in a body-centered cubic geometry to two equivalent O(2), two equivalent O(3), and four equivalent O(1) atoms. In the second Nd site, Nd(2) is bonded to one O(4), two equivalent O(1), two equivalent O(2), and two equivalent O(3) atoms to form distorted NdO7 hexagonal pyramids that share corners with three equivalent Nb(1)O5 trigonal bipyramids,  an edgeedge with one Nd(2)O7 hexagonal pyramid, and  an edgeedge with one Nb(1)O5 trigonal bipyramid. Nb(1) is bonded to one O(4), two equivalent O(1), and two equivalent O(2) atoms to form distorted NbO5 trigonal bipyramids that share corners with three equivalent Nd(2)O7 hexagonal pyramids and  an edgeedge with one Nd(2)O7 hexagonal pyramid. There are four inequivalent O sites. In the first O site, O(1) is bonded to one Nd(2), two equivalent Nd(1), and one Nb(1) atom to form distorted ONd3Nb tetrahedra that share corners with two equivalent O(1)Nd3Nb tetrahedra, corners with four equivalent O(3)Nd4 tetrahedra,  an edgeedge with one O(3)Nd4 tetrahedra, and edges with three equivalent O(1)Nd3Nb tetrahedra. In the second O site, O(2) is bonded in a 5-coordinate geometry to two equivalent K(1), one Nd(1), one Nd(2), and one Nb(1) atom. 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 eight equivalent O(1)Nd3Nb tetrahedra, edges with two equivalent O(1)Nd3Nb tetrahedra, and edges with two equivalent O(3)Nd4 tetrahedra. In the fourth O site, O(4) is bonded in a 5-coordinate geometry to three equivalent K(1), one Nd(2), and one Nb(1) atom. is represented by the CIF file [CIF]
data_KNd2NbO6
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   6.967
_cell_length_b   6.967
_cell_length_c   8.842
_cell_angle_alpha   75.589
_cell_angle_beta   75.589
_cell_angle_gamma   48.853
_symmetry_Int_Tables_number   1
_cell_volume   310.874
_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
  K  K0  1  0.884  0.884  0.479  1.0
  K  K1  1  0.116  0.116  0.521  1.0
  Nd  Nd2  1  0.871  0.871  0.930  1.0
  Nd  Nd3  1  0.412  0.412  0.202  1.0
  Nd  Nd4  1  0.588  0.588  0.798  1.0
  Nd  Nd5  1  0.129  0.129  0.070  1.0
  Nb  Nb6  1  0.341  0.341  0.703  1.0
  Nb  Nb7  1  0.659  0.659  0.297  1.0
  O  O8  1  0.469  0.000  0.833  1.0
  O  O9  1  0.314  0.781  0.291  1.0
  O  O10  1  0.251  0.749  0.000  1.0
  O  O11  1  0.686  0.219  0.709  1.0
  O  O12  1  0.781  0.314  0.291  1.0
  O  O13  1  0.749  0.251  0.000  1.0
  O  O14  1  0.219  0.686  0.709  1.0
  O  O15  1  0.531  1.000  0.167  1.0
  O  O16  1  0.326  0.326  0.499  1.0
  O  O17  1  0.674  0.674  0.501  1.0
  O  O18  1  1.000  0.531  0.167  1.0
  O  O19  1  0.000  0.469  0.833  1.0
[/CIF]
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