K3ZnCPO7 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(4) atoms. In the second K site, K(2) is bonded to one O(1), one O(2), one O(3), one O(5), one O(6), and two equivalent O(4) atoms to form distorted KO7 pentagonal bipyramids that share  a cornercorner with one Zn(1)O6 octahedra, corners with two equivalent K(2)O7 pentagonal bipyramids, corners with two equivalent P(1)O4 tetrahedra,  an edgeedge with one Zn(1)O6 octahedra,  an edgeedge with one K(2)O7 pentagonal bipyramid,  an edgeedge with one P(1)O4 tetrahedra,  a faceface with one Zn(1)O6 octahedra, and  a faceface with one K(2)O7 pentagonal bipyramid. The corner-sharing octahedral tilt angles are 73°. Zn(1) is bonded to one O(2), one O(3), one O(5), one O(6), and two equivalent O(4) atoms to form distorted ZnO6 octahedra that share corners with two equivalent K(2)O7 pentagonal bipyramids, corners with four equivalent P(1)O4 tetrahedra, edges with two equivalent K(2)O7 pentagonal bipyramids, and faces with two equivalent K(2)O7 pentagonal bipyramids. 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(5), one O(6), and two equivalent O(4) atoms to form PO4 tetrahedra that share corners with four equivalent Zn(1)O6 octahedra, corners with four equivalent K(2)O7 pentagonal bipyramids, and edges with two equivalent K(2)O7 pentagonal bipyramids. The corner-sharing octahedral tilt angles range from 30-43°. 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 Zn(1), and one C(1) atom. In the third O site, O(3) is bonded in a distorted single-bond geometry to one K(1), two equivalent K(2), one Zn(1), and one C(1) atom. In the fourth O site, O(4) is bonded in a 5-coordinate geometry to one K(1), two equivalent K(2), one Zn(1), and one P(1) atom. In the fifth O site, O(5) is bonded in a 4-coordinate geometry to two equivalent K(2), one Zn(1), and one P(1) atom. In the sixth O site, O(6) is bonded in a distorted rectangular see-saw-like geometry to two equivalent K(2), one Zn(1), and one P(1) atom.
K3ZnCPO7 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(4) atoms. The K(1)-O(2) bond length is 2.82 Å. The K(1)-O(3) bond length is 2.84 Å. There is one shorter (2.81 Å) and one longer (2.83 Å) K(1)-O(1) bond length. Both K(1)-O(4) bond lengths are 2.78 Å. In the second K site, K(2) is bonded to one O(1), one O(2), one O(3), one O(5), one O(6), and two equivalent O(4) atoms to form distorted KO7 pentagonal bipyramids that share  a cornercorner with one Zn(1)O6 octahedra, corners with two equivalent K(2)O7 pentagonal bipyramids, corners with two equivalent P(1)O4 tetrahedra,  an edgeedge with one Zn(1)O6 octahedra,  an edgeedge with one K(2)O7 pentagonal bipyramid,  an edgeedge with one P(1)O4 tetrahedra,  a faceface with one Zn(1)O6 octahedra, and  a faceface with one K(2)O7 pentagonal bipyramid. The corner-sharing octahedral tilt angles are 73°. The K(2)-O(1) bond length is 2.75 Å. The K(2)-O(2) bond length is 2.78 Å. The K(2)-O(3) bond length is 2.68 Å. The K(2)-O(5) bond length is 2.80 Å. The K(2)-O(6) bond length is 2.62 Å. There is one shorter (2.89 Å) and one longer (2.90 Å) K(2)-O(4) bond length. Zn(1) is bonded to one O(2), one O(3), one O(5), one O(6), and two equivalent O(4) atoms to form distorted ZnO6 octahedra that share corners with two equivalent K(2)O7 pentagonal bipyramids, corners with four equivalent P(1)O4 tetrahedra, edges with two equivalent K(2)O7 pentagonal bipyramids, and faces with two equivalent K(2)O7 pentagonal bipyramids. The Zn(1)-O(2) bond length is 2.24 Å. The Zn(1)-O(3) bond length is 2.37 Å. The Zn(1)-O(5) bond length is 2.01 Å. The Zn(1)-O(6) bond length is 2.05 Å. Both Zn(1)-O(4) bond lengths are 2.27 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 1.30 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(5), one O(6), and two equivalent O(4) atoms to form PO4 tetrahedra that share corners with four equivalent Zn(1)O6 octahedra, corners with four equivalent K(2)O7 pentagonal bipyramids, and edges with two equivalent K(2)O7 pentagonal bipyramids. The corner-sharing octahedral tilt angles range from 30-43°. The P(1)-O(5) bond length is 1.57 Å. The P(1)-O(6) bond length is 1.55 Å. Both P(1)-O(4) 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 Zn(1), and one C(1) atom. In the third O site, O(3) is bonded in a distorted single-bond geometry to one K(1), two equivalent K(2), one Zn(1), and one C(1) atom. In the fourth O site, O(4) is bonded in a 5-coordinate geometry to one K(1), two equivalent K(2), one Zn(1), and one P(1) atom. In the fifth O site, O(5) is bonded in a 4-coordinate geometry to two equivalent K(2), one Zn(1), and one P(1) atom. In the sixth O site, O(6) is bonded in a distorted rectangular see-saw-like geometry to two equivalent K(2), one Zn(1), and one P(1) atom.