KNbV2O8 crystallizes in the orthorhombic Pnma space group. K(1) is bonded in a 11-coordinate geometry to one O(5), two equivalent O(1), two equivalent O(3), two equivalent O(6), and four equivalent O(2) atoms. Nb(1) is bonded to one O(3), one O(4), two equivalent O(1), and two equivalent O(2) atoms to form NbO6 octahedra that share corners with three equivalent V(1)O4 tetrahedra and corners with three equivalent V(2)O4 tetrahedra. There are two inequivalent V sites. In the first V site, V(1) is bonded to one O(3), one O(5), and two equivalent O(1) atoms to form VO4 tetrahedra that share corners with three equivalent Nb(1)O6 octahedra. The corner-sharing octahedral tilt angles range from 28-32°. In the second V site, V(2) is bonded to one O(4), one O(6), and two equivalent O(2) atoms to form VO4 tetrahedra that share corners with three equivalent Nb(1)O6 octahedra. The corner-sharing octahedral tilt angles range from 18-37°. There are six inequivalent O sites. In the first O site, O(3) is bonded in a bent 150 degrees geometry to two equivalent K(1), one Nb(1), and one V(1) atom. In the second O site, O(4) is bonded in a bent 150 degrees geometry to one Nb(1) and one V(2) atom. In the third O site, O(5) is bonded in a distorted single-bond geometry to one K(1) and one V(1) atom. In the fourth O site, O(6) is bonded in a single-bond geometry to two equivalent K(1) and one V(2) atom. In the fifth O site, O(1) is bonded in a distorted bent 150 degrees geometry to one K(1), one Nb(1), and one V(1) atom. In the sixth O site, O(2) is bonded in a distorted bent 150 degrees geometry to two equivalent K(1), one Nb(1), and one V(2) atom.
KNbV2O8 crystallizes in the orthorhombic Pnma space group. K(1) is bonded in a 11-coordinate geometry to one O(5), two equivalent O(1), two equivalent O(3), two equivalent O(6), and four equivalent O(2) atoms. The K(1)-O(5) bond length is 2.69 Å. Both K(1)-O(1) bond lengths are 3.03 Å. Both K(1)-O(3) bond lengths are 3.32 Å. Both K(1)-O(6) bond lengths are 3.08 Å. There are two shorter (3.14 Å) and two longer (3.25 Å) K(1)-O(2) bond lengths. Nb(1) is bonded to one O(3), one O(4), two equivalent O(1), and two equivalent O(2) atoms to form NbO6 octahedra that share corners with three equivalent V(1)O4 tetrahedra and corners with three equivalent V(2)O4 tetrahedra. The Nb(1)-O(3) bond length is 1.98 Å. The Nb(1)-O(4) bond length is 2.01 Å. Both Nb(1)-O(1) bond lengths are 2.03 Å. Both Nb(1)-O(2) bond lengths are 2.00 Å. There are two inequivalent V sites. In the first V site, V(1) is bonded to one O(3), one O(5), and two equivalent O(1) atoms to form VO4 tetrahedra that share corners with three equivalent Nb(1)O6 octahedra. The corner-sharing octahedral tilt angles range from 28-32°. The V(1)-O(3) bond length is 1.81 Å. The V(1)-O(5) bond length is 1.64 Å. Both V(1)-O(1) bond lengths are 1.78 Å. In the second V site, V(2) is bonded to one O(4), one O(6), and two equivalent O(2) atoms to form VO4 tetrahedra that share corners with three equivalent Nb(1)O6 octahedra. The corner-sharing octahedral tilt angles range from 18-37°. The V(2)-O(4) bond length is 1.76 Å. The V(2)-O(6) bond length is 1.64 Å. Both V(2)-O(2) bond lengths are 1.80 Å. There are six inequivalent O sites. In the first O site, O(3) is bonded in a bent 150 degrees geometry to two equivalent K(1), one Nb(1), and one V(1) atom. In the second O site, O(4) is bonded in a bent 150 degrees geometry to one Nb(1) and one V(2) atom. In the third O site, O(5) is bonded in a distorted single-bond geometry to one K(1) and one V(1) atom. In the fourth O site, O(6) is bonded in a single-bond geometry to two equivalent K(1) and one V(2) atom. In the fifth O site, O(1) is bonded in a distorted bent 150 degrees geometry to one K(1), one Nb(1), and one V(1) atom. In the sixth O site, O(2) is bonded in a distorted bent 150 degrees geometry to two equivalent K(1), one Nb(1), and one V(2) atom.