K3VCPO7 crystallizes in the monoclinic P2_1/m space group. There are two inequivalent K sites. In the first K site, K(1) is bonded in a 6-coordinate geometry to one O(2), one O(3), two equivalent O(1), and two equivalent O(6) atoms. In the second K site, K(2) is bonded in a 7-coordinate geometry to one O(1), one O(2), one O(3), one O(4), one O(5), and two equivalent O(6) atoms. V(1) is bonded to one O(2), one O(3), one O(4), one O(5), and two equivalent O(6) atoms to form VO6 octahedra that share corners with four equivalent P(1)O4 tetrahedra. C(1) is bonded in a trigonal planar geometry to one O(1), one O(2), and one O(3) atom. P(1) is bonded to one O(4), one O(5), and two equivalent O(6) atoms to form PO4 tetrahedra that share corners with four equivalent V(1)O6 octahedra. The corner-sharing octahedral tilt angles range from 16-42°. There are six inequivalent O sites. In the first O site, O(1) is bonded in a distorted single-bond geometry to two equivalent K(1), two equivalent K(2), and one C(1) atom. In the second O site, O(2) is bonded in a 5-coordinate geometry to one K(1), two equivalent K(2), one V(1), and one C(1) atom. In the third O site, O(3) is bonded in a 5-coordinate geometry to one K(1), two equivalent K(2), one V(1), and one C(1) atom. In the fourth O site, O(4) is bonded in a 4-coordinate geometry to two equivalent K(2), one V(1), and one P(1) atom. In the fifth O site, O(5) is bonded in a distorted rectangular see-saw-like geometry to two equivalent K(2), one V(1), and one P(1) atom. In the sixth O site, O(6) is bonded in a 5-coordinate geometry to one K(1), two equivalent K(2), one V(1), and one P(1) atom.
K3VCPO7 crystallizes in the monoclinic P2_1/m space group. There are two inequivalent K sites. In the first K site, K(1) is bonded in a 6-coordinate geometry to one O(2), one O(3), two equivalent O(1), and two equivalent O(6) atoms. The K(1)-O(2) bond length is 2.73 Å. The K(1)-O(3) bond length is 2.81 Å. There is one shorter (2.82 Å) and one longer (2.89 Å) K(1)-O(1) bond length. Both K(1)-O(6) bond lengths are 2.75 Å. In the second K site, K(2) is bonded in a 7-coordinate geometry to one O(1), one O(2), one O(3), one O(4), one O(5), and two equivalent O(6) atoms. The K(2)-O(1) bond length is 2.81 Å. The K(2)-O(2) bond length is 2.89 Å. The K(2)-O(3) bond length is 2.79 Å. The K(2)-O(4) bond length is 2.80 Å. The K(2)-O(5) bond length is 2.68 Å. There is one shorter (2.86 Å) and one longer (2.94 Å) K(2)-O(6) bond length. V(1) is bonded to one O(2), one O(3), one O(4), one O(5), and two equivalent O(6) atoms to form VO6 octahedra that share corners with four equivalent P(1)O4 tetrahedra. The V(1)-O(2) bond length is 2.20 Å. The V(1)-O(3) bond length is 2.24 Å. The V(1)-O(4) bond length is 2.17 Å. The V(1)-O(5) bond length is 2.16 Å. Both V(1)-O(6) bond lengths are 2.25 Å. C(1) is bonded in a trigonal planar geometry to one O(1), one O(2), and one O(3) atom. The C(1)-O(1) bond length is 1.29 Å. The C(1)-O(2) bond length is 1.31 Å. The C(1)-O(3) bond length is 1.31 Å. P(1) is bonded to one O(4), one O(5), and two equivalent O(6) atoms to form PO4 tetrahedra that share corners with four equivalent V(1)O6 octahedra. The corner-sharing octahedral tilt angles range from 16-42°. The P(1)-O(4) bond length is 1.56 Å. The P(1)-O(5) bond length is 1.55 Å. Both P(1)-O(6) bond lengths are 1.56 Å. There are six inequivalent O sites. In the first O site, O(1) is bonded in a distorted single-bond geometry to two equivalent K(1), two equivalent K(2), and one C(1) atom. In the second O site, O(2) is bonded in a 5-coordinate geometry to one K(1), two equivalent K(2), one V(1), and one C(1) atom. In the third O site, O(3) is bonded in a 5-coordinate geometry to one K(1), two equivalent K(2), one V(1), and one C(1) atom. In the fourth O site, O(4) is bonded in a 4-coordinate geometry to two equivalent K(2), one V(1), and one P(1) atom. In the fifth O site, O(5) is bonded in a distorted rectangular see-saw-like geometry to two equivalent K(2), one V(1), and one P(1) atom. In the sixth O site, O(6) is bonded in a 5-coordinate geometry to one K(1), two equivalent K(2), one V(1), and one P(1) atom.