NiZnP2O7 crystallizes in the triclinic P-1 space group. Ni(1) is bonded to one O(1), one O(2), one O(3), one O(5), and one O(7) atom to form NiO5 trigonal bipyramids that share corners with two equivalent P(2)O4 tetrahedra, corners with three equivalent P(1)O4 tetrahedra, and edges with two equivalent Zn(1)O6 octahedra. Zn(1) is bonded to one O(1), one O(3), one O(5), one O(7), and two equivalent O(4) atoms to form distorted ZnO6 octahedra that share corners with two equivalent P(1)O4 tetrahedra, corners with four equivalent P(2)O4 tetrahedra,  an edgeedge with one Zn(1)O6 octahedra, and edges with two equivalent Ni(1)O5 trigonal bipyramids. There are two inequivalent P sites. In the first P site, P(1) is bonded to one O(1), one O(2), one O(3), and one O(6) atom to form PO4 tetrahedra that share corners with two equivalent Zn(1)O6 octahedra,  a cornercorner with one P(2)O4 tetrahedra, and corners with three equivalent Ni(1)O5 trigonal bipyramids. The corner-sharing octahedral tilt angles range from 50-54°. In the second P site, P(2) is bonded to one O(4), one O(5), one O(6), and one O(7) atom to form PO4 tetrahedra that share corners with four equivalent Zn(1)O6 octahedra,  a cornercorner with one P(1)O4 tetrahedra, and corners with two equivalent Ni(1)O5 trigonal bipyramids. The corner-sharing octahedral tilt angles range from 34-55°. There are seven inequivalent O sites. In the first O site, O(1) is bonded in a distorted trigonal planar geometry to one Ni(1), one Zn(1), and one P(1) atom. In the second O site, O(2) is bonded in a bent 150 degrees geometry to one Ni(1) and one P(1) atom. In the third O site, O(3) is bonded in a distorted trigonal planar geometry to one Ni(1), one Zn(1), and one P(1) atom. In the fourth O site, O(4) is bonded in a distorted trigonal planar geometry to two equivalent Zn(1) and one P(2) atom. In the fifth O site, O(5) is bonded in a 3-coordinate geometry to one Ni(1), one Zn(1), and one P(2) atom. In the sixth O site, O(6) is bonded in a bent 150 degrees geometry to one P(1) and one P(2) atom. In the seventh O site, O(7) is bonded in a distorted trigonal planar geometry to one Ni(1), one Zn(1), and one P(2) atom.
NiZnP2O7 crystallizes in the triclinic P-1 space group. Ni(1) is bonded to one O(1), one O(2), one O(3), one O(5), and one O(7) atom to form NiO5 trigonal bipyramids that share corners with two equivalent P(2)O4 tetrahedra, corners with three equivalent P(1)O4 tetrahedra, and edges with two equivalent Zn(1)O6 octahedra. The Ni(1)-O(1) bond length is 2.04 Å. The Ni(1)-O(2) bond length is 1.98 Å. The Ni(1)-O(3) bond length is 2.05 Å. The Ni(1)-O(5) bond length is 2.10 Å. The Ni(1)-O(7) bond length is 2.07 Å. Zn(1) is bonded to one O(1), one O(3), one O(5), one O(7), and two equivalent O(4) atoms to form distorted ZnO6 octahedra that share corners with two equivalent P(1)O4 tetrahedra, corners with four equivalent P(2)O4 tetrahedra,  an edgeedge with one Zn(1)O6 octahedra, and edges with two equivalent Ni(1)O5 trigonal bipyramids. The Zn(1)-O(1) bond length is 2.12 Å. The Zn(1)-O(3) bond length is 2.14 Å. The Zn(1)-O(5) bond length is 2.26 Å. The Zn(1)-O(7) bond length is 2.07 Å. There is one shorter (2.00 Å) and one longer (2.31 Å) Zn(1)-O(4) bond length. There are two inequivalent P sites. In the first P site, P(1) is bonded to one O(1), one O(2), one O(3), and one O(6) atom to form PO4 tetrahedra that share corners with two equivalent Zn(1)O6 octahedra,  a cornercorner with one P(2)O4 tetrahedra, and corners with three equivalent Ni(1)O5 trigonal bipyramids. The corner-sharing octahedral tilt angles range from 50-54°. The P(1)-O(1) bond length is 1.55 Å. The P(1)-O(2) bond length is 1.51 Å. The P(1)-O(3) bond length is 1.54 Å. The P(1)-O(6) bond length is 1.61 Å. In the second P site, P(2) is bonded to one O(4), one O(5), one O(6), and one O(7) atom to form PO4 tetrahedra that share corners with four equivalent Zn(1)O6 octahedra,  a cornercorner with one P(1)O4 tetrahedra, and corners with two equivalent Ni(1)O5 trigonal bipyramids. The corner-sharing octahedral tilt angles range from 34-55°. The P(2)-O(4) bond length is 1.53 Å. The P(2)-O(5) bond length is 1.54 Å. The P(2)-O(6) bond length is 1.59 Å. The P(2)-O(7) bond length is 1.54 Å. There are seven inequivalent O sites. In the first O site, O(1) is bonded in a distorted trigonal planar geometry to one Ni(1), one Zn(1), and one P(1) atom. In the second O site, O(2) is bonded in a bent 150 degrees geometry to one Ni(1) and one P(1) atom. In the third O site, O(3) is bonded in a distorted trigonal planar geometry to one Ni(1), one Zn(1), and one P(1) atom. In the fourth O site, O(4) is bonded in a distorted trigonal planar geometry to two equivalent Zn(1) and one P(2) atom. In the fifth O site, O(5) is bonded in a 3-coordinate geometry to one Ni(1), one Zn(1), and one P(2) atom. In the sixth O site, O(6) is bonded in a bent 150 degrees geometry to one P(1) and one P(2) atom. In the seventh O site, O(7) is bonded in a distorted trigonal planar geometry to one Ni(1), one Zn(1), and one P(2) atom.