KNdNb4O12 crystallizes in the orthorhombic Amm2 space group. K(1) is bonded in a 10-coordinate geometry to two equivalent O(2), four equivalent O(1), and four equivalent O(5) atoms. Nd(1) is bonded in a 10-coordinate geometry to two equivalent O(2), two equivalent O(3), two equivalent O(4), and four equivalent O(1) atoms. Nb(1) is bonded to one O(2), one O(3), one O(4), one O(5), and two equivalent O(1) atoms to form corner-sharing NbO6 octahedra. The corner-sharing octahedral tilt angles range from 11-30°. There are five inequivalent O sites. In the first O site, O(1) is bonded in a 2-coordinate geometry to one K(1), one Nd(1), and two equivalent Nb(1) atoms. In the second O site, O(2) is bonded in a distorted square co-planar geometry to one K(1), one Nd(1), and two equivalent Nb(1) atoms. In the third O site, O(3) is bonded in a 3-coordinate geometry to one Nd(1) and two equivalent Nb(1) atoms. In the fourth O site, O(4) is bonded in a distorted T-shaped geometry to one Nd(1) and two equivalent Nb(1) atoms. In the fifth O site, O(5) is bonded in a distorted square co-planar geometry to two equivalent K(1) and two equivalent Nb(1) atoms.
KNdNb4O12 crystallizes in the orthorhombic Amm2 space group. K(1) is bonded in a 10-coordinate geometry to two equivalent O(2), four equivalent O(1), and four equivalent O(5) atoms. Both K(1)-O(2) bond lengths are 2.81 Å. All K(1)-O(1) bond lengths are 2.78 Å. There are two shorter (2.76 Å) and two longer (2.89 Å) K(1)-O(5) bond lengths. Nd(1) is bonded in a 10-coordinate geometry to two equivalent O(2), two equivalent O(3), two equivalent O(4), and four equivalent O(1) atoms. Both Nd(1)-O(2) bond lengths are 2.66 Å. Both Nd(1)-O(3) bond lengths are 2.47 Å. Both Nd(1)-O(4) bond lengths are 2.43 Å. All Nd(1)-O(1) bond lengths are 2.87 Å. Nb(1) is bonded to one O(2), one O(3), one O(4), one O(5), and two equivalent O(1) atoms to form corner-sharing NbO6 octahedra. The corner-sharing octahedral tilt angles range from 11-30°. The Nb(1)-O(2) bond length is 2.02 Å. The Nb(1)-O(3) bond length is 2.04 Å. The Nb(1)-O(4) bond length is 2.05 Å. The Nb(1)-O(5) bond length is 1.99 Å. There is one shorter (1.95 Å) and one longer (2.06 Å) Nb(1)-O(1) bond length. There are five inequivalent O sites. In the first O site, O(1) is bonded in a 2-coordinate geometry to one K(1), one Nd(1), and two equivalent Nb(1) atoms. In the second O site, O(2) is bonded in a distorted square co-planar geometry to one K(1), one Nd(1), and two equivalent Nb(1) atoms. In the third O site, O(3) is bonded in a 3-coordinate geometry to one Nd(1) and two equivalent Nb(1) atoms. In the fourth O site, O(4) is bonded in a distorted T-shaped geometry to one Nd(1) and two equivalent Nb(1) atoms. In the fifth O site, O(5) is bonded in a distorted square co-planar geometry to two equivalent K(1) and two equivalent Nb(1) atoms.