CrNi(PO4)2 crystallizes in the monoclinic P2_1/m space group. Cr(1) is bonded to one O(1), one O(5), two equivalent O(3), and two equivalent O(4) atoms to form CrO6 octahedra that share corners with four equivalent Ni(1)O6 octahedra,  a cornercorner with one P(2)O4 tetrahedra, corners with three equivalent P(1)O4 tetrahedra, and  an edgeedge with one P(2)O4 tetrahedra. The corner-sharing octahedral tilt angles range from 48-51°. Ni(1) is bonded to one O(2), one O(6), two equivalent O(3), and two equivalent O(4) atoms to form distorted NiO6 octahedra that share corners with four equivalent Cr(1)O6 octahedra,  a cornercorner with one P(1)O4 tetrahedra, corners with three equivalent P(2)O4 tetrahedra, and  an edgeedge with one P(1)O4 tetrahedra. The corner-sharing octahedral tilt angles range from 48-51°. There are two inequivalent P sites. In the first P site, P(1) is bonded to one O(1), one O(2), and two equivalent O(3) atoms to form PO4 tetrahedra that share  a cornercorner with one Ni(1)O6 octahedra, corners with three equivalent Cr(1)O6 octahedra, and  an edgeedge with one Ni(1)O6 octahedra. The corner-sharing octahedral tilt angles range from 47-55°. In the second P site, P(2) is bonded to one O(5), one O(6), and two equivalent O(4) atoms to form PO4 tetrahedra that share  a cornercorner with one Cr(1)O6 octahedra, corners with three equivalent Ni(1)O6 octahedra, and  an edgeedge with one Cr(1)O6 octahedra. The corner-sharing octahedral tilt angles range from 41-59°. There are six inequivalent O sites. In the first O site, O(1) is bonded in a distorted bent 120 degrees geometry to one Cr(1) and one P(1) atom. In the second O site, O(2) is bonded in a bent 120 degrees geometry to one Ni(1) and one P(1) atom. In the third O site, O(3) is bonded in a 3-coordinate geometry to one Cr(1), one Ni(1), and one P(1) atom. In the fourth O site, O(4) is bonded in a distorted trigonal planar geometry to one Cr(1), one Ni(1), and one P(2) atom. In the fifth O site, O(5) is bonded in a bent 150 degrees geometry to one Cr(1) and one P(2) atom. In the sixth O site, O(6) is bonded in a bent 150 degrees geometry to one Ni(1) and one P(2) atom.
CrNi(PO4)2 crystallizes in the monoclinic P2_1/m space group. Cr(1) is bonded to one O(1), one O(5), two equivalent O(3), and two equivalent O(4) atoms to form CrO6 octahedra that share corners with four equivalent Ni(1)O6 octahedra,  a cornercorner with one P(2)O4 tetrahedra, corners with three equivalent P(1)O4 tetrahedra, and  an edgeedge with one P(2)O4 tetrahedra. The corner-sharing octahedral tilt angles range from 48-51°. The Cr(1)-O(1) bond length is 1.97 Å. The Cr(1)-O(5) bond length is 1.95 Å. Both Cr(1)-O(3) bond lengths are 1.99 Å. Both Cr(1)-O(4) bond lengths are 2.03 Å. Ni(1) is bonded to one O(2), one O(6), two equivalent O(3), and two equivalent O(4) atoms to form distorted NiO6 octahedra that share corners with four equivalent Cr(1)O6 octahedra,  a cornercorner with one P(1)O4 tetrahedra, corners with three equivalent P(2)O4 tetrahedra, and  an edgeedge with one P(1)O4 tetrahedra. The corner-sharing octahedral tilt angles range from 48-51°. The Ni(1)-O(2) bond length is 1.96 Å. The Ni(1)-O(6) bond length is 1.97 Å. Both Ni(1)-O(3) bond lengths are 2.32 Å. Both Ni(1)-O(4) bond lengths are 2.04 Å. There are two inequivalent P sites. In the first P site, P(1) is bonded to one O(1), one O(2), and two equivalent O(3) atoms to form PO4 tetrahedra that share  a cornercorner with one Ni(1)O6 octahedra, corners with three equivalent Cr(1)O6 octahedra, and  an edgeedge with one Ni(1)O6 octahedra. The corner-sharing octahedral tilt angles range from 47-55°. The P(1)-O(1) bond length is 1.53 Å. The P(1)-O(2) bond length is 1.52 Å. Both P(1)-O(3) bond lengths are 1.58 Å. In the second P site, P(2) is bonded to one O(5), one O(6), and two equivalent O(4) atoms to form PO4 tetrahedra that share  a cornercorner with one Cr(1)O6 octahedra, corners with three equivalent Ni(1)O6 octahedra, and  an edgeedge with one Cr(1)O6 octahedra. The corner-sharing octahedral tilt angles range from 41-59°. The P(2)-O(5) bond length is 1.52 Å. The P(2)-O(6) bond length is 1.51 Å. Both P(2)-O(4) bond lengths are 1.59 Å. There are six inequivalent O sites. In the first O site, O(1) is bonded in a distorted bent 120 degrees geometry to one Cr(1) and one P(1) atom. In the second O site, O(2) is bonded in a bent 120 degrees geometry to one Ni(1) and one P(1) atom. In the third O site, O(3) is bonded in a 3-coordinate geometry to one Cr(1), one Ni(1), and one P(1) atom. In the fourth O site, O(4) is bonded in a distorted trigonal planar geometry to one Cr(1), one Ni(1), and one P(2) atom. In the fifth O site, O(5) is bonded in a bent 150 degrees geometry to one Cr(1) and one P(2) atom. In the sixth O site, O(6) is bonded in a bent 150 degrees geometry to one Ni(1) and one P(2) atom.