ZrTa(PO4)3 crystallizes in the trigonal R3c space group. Zr(1) is bonded to three equivalent O(1) and three equivalent O(3) atoms to form ZrO6 octahedra that share corners with six equivalent P(1)O4 tetrahedra. Ta(1) is bonded to three equivalent O(2) and three equivalent O(4) atoms to form TaO6 octahedra that share corners with six equivalent P(1)O4 tetrahedra. P(1) is bonded to one O(1), one O(2), one O(3), and one O(4) atom to form PO4 tetrahedra that share corners with two equivalent Zr(1)O6 octahedra and corners with two equivalent Ta(1)O6 octahedra. The corner-sharing octahedral tilt angles range from 22-28°. There are four inequivalent O sites. In the first O site, O(2) is bonded in a bent 150 degrees geometry to one Ta(1) and one P(1) atom. In the second O site, O(3) is bonded in a bent 150 degrees geometry to one Zr(1) and one P(1) atom. In the third O site, O(4) is bonded in a bent 150 degrees geometry to one Ta(1) and one P(1) atom. In the fourth O site, O(1) is bonded in a bent 150 degrees geometry to one Zr(1) and one P(1) atom.
ZrTa(PO4)3 crystallizes in the trigonal R3c space group. Zr(1) is bonded to three equivalent O(1) and three equivalent O(3) atoms to form ZrO6 octahedra that share corners with six equivalent P(1)O4 tetrahedra. All Zr(1)-O(1) bond lengths are 2.09 Å. All Zr(1)-O(3) bond lengths are 2.07 Å. Ta(1) is bonded to three equivalent O(2) and three equivalent O(4) atoms to form TaO6 octahedra that share corners with six equivalent P(1)O4 tetrahedra. All Ta(1)-O(2) bond lengths are 2.02 Å. All Ta(1)-O(4) bond lengths are 1.97 Å. P(1) is bonded to one O(1), one O(2), one O(3), and one O(4) atom to form PO4 tetrahedra that share corners with two equivalent Zr(1)O6 octahedra and corners with two equivalent Ta(1)O6 octahedra. The corner-sharing octahedral tilt angles range from 22-28°. The P(1)-O(1) bond length is 1.51 Å. The P(1)-O(2) bond length is 1.56 Å. The P(1)-O(3) bond length is 1.53 Å. The P(1)-O(4) bond length is 1.57 Å. There are four inequivalent O sites. In the first O site, O(2) is bonded in a bent 150 degrees geometry to one Ta(1) and one P(1) atom. In the second O site, O(3) is bonded in a bent 150 degrees geometry to one Zr(1) and one P(1) atom. In the third O site, O(4) is bonded in a bent 150 degrees geometry to one Ta(1) and one P(1) atom. In the fourth O site, O(1) is bonded in a bent 150 degrees geometry to one Zr(1) and one P(1) atom.