Materials Data on Ti5Nb(PO4)6 by Materials Project
Ti5Nb(PO4)6 crystallizes in the trigonal R3 space group. The structure is three-dimensional. there are five inequivalent Ti+3.20+ sites. In the first Ti+3.20+ site, Ti+3.20+ is bonded to six O2- atoms to form TiO6 octahedra that share corners with six PO4 tetrahedra, a faceface with one TiO6 octahedra, and a faceface with one NbO6 octahedra. There are three shorter (2.14 Å) and three longer (2.22 Å) Ti–O bond lengths. In the second Ti+3.20+ site, Ti+3.20+ is bonded to six O2- atoms to form TiO6 octahedra that share corners with six PO4 tetrahedra and faces with two TiO6 octahedra. There are three shorter (2.15 Å) and three longer (2.18 Å) Ti–O bond lengths. In the third Ti+3.20+ site, Ti+3.20+ is bonded to six O2- atoms to form TiO6 octahedra that share corners with six PO4 tetrahedra and a faceface with one TiO6 octahedra. There are three shorter (1.96 Å) and three longer (2.09 Å) Ti–O bond lengths. In the fourth Ti+3.20+ site, Ti+3.20+ is bonded to six O2- atoms to form TiO6 octahedra that share corners with six PO4 tetrahedra and a faceface with one TiO6 octahedra. There are three shorter (1.97 Å) and three longer (2.06 Å) Ti–O bond lengths. In the fifth Ti+3.20+ site, Ti+3.20+ is bonded to six O2- atoms to form TiO6 octahedra that share corners with six PO4 tetrahedra and a faceface with one TiO6 octahedra. There are three shorter (1.96 Å) and three longer (2.08 Å) Ti–O bond lengths. Nb2+ is bonded to six O2- atoms to form NbO6 octahedra that share corners with six PO4 tetrahedra and a faceface with one TiO6 octahedra. There are three shorter (2.05 Å) and three longer (2.11 Å) Nb–O bond lengths. There are two inequivalent P5+ sites. In the first P5+ site, P5+ is bonded to four O2- atoms to form PO4 tetrahedra that share a cornercorner with one NbO6 octahedra and corners with five TiO6 octahedra. The corner-sharing octahedra tilt angles range from 25–50°. There are a spread of P–O bond distances ranging from 1.53–1.58 Å. In the second P5+ site, P5+ is bonded to four O2- atoms to form PO4 tetrahedra that share a cornercorner with one NbO6 octahedra and corners with five TiO6 octahedra. The corner-sharing octahedra tilt angles range from 26–49°. There are a spread of P–O bond distances ranging from 1.52–1.58 Å. There are eight inequivalent O2- sites. In the first O2- site, O2- is bonded in a bent 150 degrees geometry to one Ti+3.20+ and one P5+ atom. In the second O2- site, O2- is bonded in a 3-coordinate geometry to two Ti+3.20+ and one P5+ atom. In the third O2- site, O2- is bonded in a bent 150 degrees geometry to one Nb2+ and one P5+ atom. In the fourth O2- site, O2- is bonded in a 3-coordinate geometry to two Ti+3.20+ and one P5+ atom. In the fifth O2- site, O2- is bonded in a bent 150 degrees geometry to one Ti+3.20+ and one P5+ atom. In the sixth O2- site, O2- is bonded in a 1-coordinate geometry to one Ti+3.20+, one Nb2+, and one P5+ atom. In the seventh O2- site, O2- is bonded in a 3-coordinate geometry to two Ti+3.20+ and one P5+ atom. In the eighth O2- site, O2- is bonded in a bent 150 degrees geometry to one Ti+3.20+ and one P5+ atom.