Zr2O(PO4)2 crystallizes in the monoclinic C2/m space group. There are two inequivalent Zr sites. In the first Zr site, Zr(1) is bonded to one O(4), one O(6), two equivalent O(2), and two equivalent O(7) atoms to form ZrO6 octahedra that share  a cornercorner with one Zr(2)O7 pentagonal bipyramid,  a cornercorner with one P(2)O4 tetrahedra, corners with three equivalent P(1)O4 tetrahedra,  an edgeedge with one Zr(1)O6 octahedra, and  an edgeedge with one Zr(2)O7 pentagonal bipyramid. In the second Zr site, Zr(2) is bonded to one O(4), one O(5), one O(7), two equivalent O(1), and two equivalent O(3) atoms to form ZrO7 pentagonal bipyramids that share  a cornercorner with one Zr(1)O6 octahedra,  a cornercorner with one P(1)O4 tetrahedra, corners with three equivalent P(2)O4 tetrahedra,  an edgeedge with one Zr(1)O6 octahedra,  an edgeedge with one Zr(2)O7 pentagonal bipyramid, and  an edgeedge with one P(1)O4 tetrahedra. The corner-sharing octahedral tilt angles are 36°. There are two inequivalent P sites. In the first P site, P(1) is bonded to one O(3), one O(4), and two equivalent O(2) atoms to form PO4 tetrahedra that share corners with three equivalent Zr(1)O6 octahedra,  a cornercorner with one Zr(2)O7 pentagonal bipyramid, and  an edgeedge with one Zr(2)O7 pentagonal bipyramid. The corner-sharing octahedral tilt angles range from 24-28°. In the second P site, P(2) is bonded to one O(5), one O(6), and two equivalent O(1) atoms to form PO4 tetrahedra that share  a cornercorner with one Zr(1)O6 octahedra and corners with three equivalent Zr(2)O7 pentagonal bipyramids. The corner-sharing octahedral tilt angles are 38°. There are seven inequivalent O sites. In the first O site, O(1) is bonded in a bent 150 degrees geometry to one Zr(2) and one P(2) atom. In the second O site, O(2) is bonded in a bent 150 degrees geometry to one Zr(1) and one P(1) atom. In the third O site, O(3) is bonded in a 3-coordinate geometry to two equivalent Zr(2) and one P(1) atom. In the fourth O site, O(4) is bonded in a 3-coordinate geometry to one Zr(1), one Zr(2), and one P(1) atom. In the fifth O site, O(5) is bonded in a bent 150 degrees geometry to one Zr(2) and one P(2) atom. In the sixth O site, O(6) is bonded in a bent 150 degrees geometry to one Zr(1) and one P(2) atom. In the seventh O site, O(7) is bonded in a distorted trigonal planar geometry to one Zr(2) and two equivalent Zr(1) atoms.
Zr2O(PO4)2 crystallizes in the monoclinic C2/m space group. There are two inequivalent Zr sites. In the first Zr site, Zr(1) is bonded to one O(4), one O(6), two equivalent O(2), and two equivalent O(7) atoms to form ZrO6 octahedra that share  a cornercorner with one Zr(2)O7 pentagonal bipyramid,  a cornercorner with one P(2)O4 tetrahedra, corners with three equivalent P(1)O4 tetrahedra,  an edgeedge with one Zr(1)O6 octahedra, and  an edgeedge with one Zr(2)O7 pentagonal bipyramid. The Zr(1)-O(4) bond length is 2.17 Å. The Zr(1)-O(6) bond length is 2.03 Å. Both Zr(1)-O(2) bond lengths are 2.08 Å. There is one shorter (2.01 Å) and one longer (2.14 Å) Zr(1)-O(7) bond length. In the second Zr site, Zr(2) is bonded to one O(4), one O(5), one O(7), two equivalent O(1), and two equivalent O(3) atoms to form ZrO7 pentagonal bipyramids that share  a cornercorner with one Zr(1)O6 octahedra,  a cornercorner with one P(1)O4 tetrahedra, corners with three equivalent P(2)O4 tetrahedra,  an edgeedge with one Zr(1)O6 octahedra,  an edgeedge with one Zr(2)O7 pentagonal bipyramid, and  an edgeedge with one P(1)O4 tetrahedra. The corner-sharing octahedral tilt angles are 36°. The Zr(2)-O(4) bond length is 2.32 Å. The Zr(2)-O(5) bond length is 2.06 Å. The Zr(2)-O(7) bond length is 2.09 Å. Both Zr(2)-O(1) bond lengths are 2.06 Å. There is one shorter (2.24 Å) and one longer (2.31 Å) Zr(2)-O(3) bond length. There are two inequivalent P sites. In the first P site, P(1) is bonded to one O(3), one O(4), and two equivalent O(2) atoms to form PO4 tetrahedra that share corners with three equivalent Zr(1)O6 octahedra,  a cornercorner with one Zr(2)O7 pentagonal bipyramid, and  an edgeedge with one Zr(2)O7 pentagonal bipyramid. The corner-sharing octahedral tilt angles range from 24-28°. The P(1)-O(3) bond length is 1.55 Å. The P(1)-O(4) bond length is 1.56 Å. Both P(1)-O(2) bond lengths are 1.51 Å. In the second P site, P(2) is bonded to one O(5), one O(6), and two equivalent O(1) atoms to form PO4 tetrahedra that share  a cornercorner with one Zr(1)O6 octahedra and corners with three equivalent Zr(2)O7 pentagonal bipyramids. The corner-sharing octahedral tilt angles are 38°. The P(2)-O(5) bond length is 1.54 Å. The P(2)-O(6) bond length is 1.53 Å. Both P(2)-O(1) bond lengths are 1.53 Å. There are seven inequivalent O sites. In the first O site, O(1) is bonded in a bent 150 degrees geometry to one Zr(2) and one P(2) atom. In the second O site, O(2) is bonded in a bent 150 degrees geometry to one Zr(1) and one P(1) atom. In the third O site, O(3) is bonded in a 3-coordinate geometry to two equivalent Zr(2) and one P(1) atom. In the fourth O site, O(4) is bonded in a 3-coordinate geometry to one Zr(1), one Zr(2), and one P(1) atom. In the fifth O site, O(5) is bonded in a bent 150 degrees geometry to one Zr(2) and one P(2) atom. In the sixth O site, O(6) is bonded in a bent 150 degrees geometry to one Zr(1) and one P(2) atom. In the seventh O site, O(7) is bonded in a distorted trigonal planar geometry to one Zr(2) and two equivalent Zr(1) atoms.