Ti5V(PO4)6 crystallizes in the trigonal R3 space group. There are five inequivalent Ti sites. In the first Ti site, Ti(1) is bonded to three equivalent O(2) and three equivalent O(6) atoms to form distorted TiO6 octahedra that share corners with three equivalent P(1)O4 tetrahedra, corners with three equivalent P(2)O4 tetrahedra,  a faceface with one Ti(4)O6 octahedra, and  a faceface with one V(1)O6 octahedra. In the second Ti site, Ti(2) is bonded to three equivalent O(4) and three equivalent O(8) atoms to form TiO6 octahedra that share corners with three equivalent P(1)O4 tetrahedra, corners with three equivalent P(2)O4 tetrahedra, and  a faceface with one Ti(3)O6 octahedra. In the third Ti site, Ti(3) is bonded to three equivalent O(4) and three equivalent O(7) atoms to form distorted TiO6 octahedra that share corners with three equivalent P(1)O4 tetrahedra, corners with three equivalent P(2)O4 tetrahedra,  a faceface with one Ti(2)O6 octahedra, and  a faceface with one Ti(5)O6 octahedra. In the fourth Ti site, Ti(4) is bonded to three equivalent O(2) and three equivalent O(5) atoms to form TiO6 octahedra that share corners with three equivalent P(1)O4 tetrahedra, corners with three equivalent P(2)O4 tetrahedra, and  a faceface with one Ti(1)O6 octahedra. In the fifth Ti site, Ti(5) is bonded to three equivalent O(1) and three equivalent O(7) atoms to form TiO6 octahedra that share corners with three equivalent P(1)O4 tetrahedra, corners with three equivalent P(2)O4 tetrahedra, and  a faceface with one Ti(3)O6 octahedra. V(1) is bonded to three equivalent O(3) and three equivalent O(6) atoms to form VO6 octahedra that share corners with three equivalent P(1)O4 tetrahedra, corners with three equivalent P(2)O4 tetrahedra, and  a faceface with one Ti(1)O6 octahedra. 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(4) atom to form PO4 tetrahedra that share  a cornercorner with one Ti(1)O6 octahedra,  a cornercorner with one Ti(2)O6 octahedra,  a cornercorner with one Ti(3)O6 octahedra,  a cornercorner with one Ti(4)O6 octahedra,  a cornercorner with one Ti(5)O6 octahedra, and  a cornercorner with one V(1)O6 octahedra. The corner-sharing octahedral tilt angles range from 26-50°. In the second P site, P(2) is bonded to one O(5), one O(6), one O(7), and one O(8) atom to form PO4 tetrahedra that share  a cornercorner with one Ti(1)O6 octahedra,  a cornercorner with one Ti(2)O6 octahedra,  a cornercorner with one Ti(3)O6 octahedra,  a cornercorner with one Ti(4)O6 octahedra,  a cornercorner with one Ti(5)O6 octahedra, and  a cornercorner with one V(1)O6 octahedra. The corner-sharing octahedral tilt angles range from 25-51°. There are eight inequivalent O sites. In the first O site, O(1) is bonded in a bent 150 degrees geometry to one Ti(5) and one P(1) atom. In the second O site, O(2) is bonded in a 3-coordinate geometry to one Ti(1), one Ti(4), and one P(1) atom. In the third O site, O(3) is bonded in a bent 150 degrees geometry to one V(1) and one P(1) atom. In the fourth O site, O(4) is bonded in a 3-coordinate geometry to one Ti(2), one Ti(3), and one P(1) atom. In the fifth O site, O(5) is bonded in a bent 150 degrees geometry to one Ti(4) and one P(2) atom. In the sixth O site, O(6) is bonded in a 3-coordinate geometry to one Ti(1), one V(1), and one P(2) atom. In the seventh O site, O(7) is bonded in a 3-coordinate geometry to one Ti(3), one Ti(5), and one P(2) atom. In the eighth O site, O(8) is bonded in a bent 150 degrees geometry to one Ti(2) and one P(2) atom.
Ti5V(PO4)6 crystallizes in the trigonal R3 space group. There are five inequivalent Ti sites. In the first Ti site, Ti(1) is bonded to three equivalent O(2) and three equivalent O(6) atoms to form distorted TiO6 octahedra that share corners with three equivalent P(1)O4 tetrahedra, corners with three equivalent P(2)O4 tetrahedra,  a faceface with one Ti(4)O6 octahedra, and  a faceface with one V(1)O6 octahedra. All Ti(1)-O(2) bond lengths are 2.14 Å. All Ti(1)-O(6) bond lengths are 2.14 Å. In the second Ti site, Ti(2) is bonded to three equivalent O(4) and three equivalent O(8) atoms to form TiO6 octahedra that share corners with three equivalent P(1)O4 tetrahedra, corners with three equivalent P(2)O4 tetrahedra, and  a faceface with one Ti(3)O6 octahedra. All Ti(2)-O(4) bond lengths are 2.04 Å. All Ti(2)-O(8) bond lengths are 1.95 Å. In the third Ti site, Ti(3) is bonded to three equivalent O(4) and three equivalent O(7) atoms to form distorted TiO6 octahedra that share corners with three equivalent P(1)O4 tetrahedra, corners with three equivalent P(2)O4 tetrahedra,  a faceface with one Ti(2)O6 octahedra, and  a faceface with one Ti(5)O6 octahedra. All Ti(3)-O(4) bond lengths are 2.15 Å. All Ti(3)-O(7) bond lengths are 2.17 Å. In the fourth Ti site, Ti(4) is bonded to three equivalent O(2) and three equivalent O(5) atoms to form TiO6 octahedra that share corners with three equivalent P(1)O4 tetrahedra, corners with three equivalent P(2)O4 tetrahedra, and  a faceface with one Ti(1)O6 octahedra. All Ti(4)-O(2) bond lengths are 2.09 Å. All Ti(4)-O(5) bond lengths are 1.93 Å. In the fifth Ti site, Ti(5) is bonded to three equivalent O(1) and three equivalent O(7) atoms to form TiO6 octahedra that share corners with three equivalent P(1)O4 tetrahedra, corners with three equivalent P(2)O4 tetrahedra, and  a faceface with one Ti(3)O6 octahedra. All Ti(5)-O(1) bond lengths are 1.95 Å. All Ti(5)-O(7) bond lengths are 2.08 Å. V(1) is bonded to three equivalent O(3) and three equivalent O(6) atoms to form VO6 octahedra that share corners with three equivalent P(1)O4 tetrahedra, corners with three equivalent P(2)O4 tetrahedra, and  a faceface with one Ti(1)O6 octahedra. All V(1)-O(3) bond lengths are 2.00 Å. All V(1)-O(6) bond lengths are 2.11 Å. 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(4) atom to form PO4 tetrahedra that share  a cornercorner with one Ti(1)O6 octahedra,  a cornercorner with one Ti(2)O6 octahedra,  a cornercorner with one Ti(3)O6 octahedra,  a cornercorner with one Ti(4)O6 octahedra,  a cornercorner with one Ti(5)O6 octahedra, and  a cornercorner with one V(1)O6 octahedra. The corner-sharing octahedral tilt angles range from 26-50°. The P(1)-O(1) bond length is 1.54 Å. The P(1)-O(2) bond length is 1.58 Å. The P(1)-O(3) bond length is 1.50 Å. The P(1)-O(4) bond length is 1.59 Å. In the second P site, P(2) is bonded to one O(5), one O(6), one O(7), and one O(8) atom to form PO4 tetrahedra that share  a cornercorner with one Ti(1)O6 octahedra,  a cornercorner with one Ti(2)O6 octahedra,  a cornercorner with one Ti(3)O6 octahedra,  a cornercorner with one Ti(4)O6 octahedra,  a cornercorner with one Ti(5)O6 octahedra, and  a cornercorner with one V(1)O6 octahedra. The corner-sharing octahedral tilt angles range from 25-51°. The P(2)-O(5) bond length is 1.53 Å. The P(2)-O(6) bond length is 1.55 Å. The P(2)-O(7) bond length is 1.58 Å. The P(2)-O(8) bond length is 1.53 Å. There are eight inequivalent O sites. In the first O site, O(1) is bonded in a bent 150 degrees geometry to one Ti(5) and one P(1) atom. In the second O site, O(2) is bonded in a 3-coordinate geometry to one Ti(1), one Ti(4), and one P(1) atom. In the third O site, O(3) is bonded in a bent 150 degrees geometry to one V(1) and one P(1) atom. In the fourth O site, O(4) is bonded in a 3-coordinate geometry to one Ti(2), one Ti(3), and one P(1) atom. In the fifth O site, O(5) is bonded in a bent 150 degrees geometry to one Ti(4) and one P(2) atom. In the sixth O site, O(6) is bonded in a 3-coordinate geometry to one Ti(1), one V(1), and one P(2) atom. In the seventh O site, O(7) is bonded in a 3-coordinate geometry to one Ti(3), one Ti(5), and one P(2) atom. In the eighth O site, O(8) is bonded in a bent 150 degrees geometry to one Ti(2) and one P(2) atom.