Materials Data on NbTl(PO4)2 by Materials Project

Abstract

NbTl(PO4)2 crystallizes in the monoclinic P2_1/c space group. The structure is three-dimensional. Nb5+ is bonded to six O2- atoms to form distorted NbO6 octahedra that share corners with five PO4 tetrahedra. There are a spread of Nb–O bond distances ranging from 1.77–2.27 Å. Tl1+ is bonded in a 6-coordinate geometry to six O2- atoms. There are a spread of Tl–O bond distances ranging from 2.60–3.19 Å. There are two inequivalent P5+ sites. In the first P5+ site, P5+ is bonded to four O2- atoms to form PO4 tetrahedra that share corners with two equivalent NbO6 octahedra and a cornercorner with one PO4 tetrahedra. The corner-sharing octahedra tilt angles range from 26–35°. There are a spread of P–O bond distances ranging from 1.49–1.64 Å. In the second P5+ site, P5+ is bonded to four O2- atoms to form PO4 tetrahedra that share corners with three equivalent NbO6 octahedra and a cornercorner with one PO4 tetrahedra. The corner-sharing octahedra tilt angles range from 15–40°. There are a spread of P–O bond distances ranging from 1.50–1.61 Å. There are eight inequivalent O2- sites. In the first O2- site, O2- is bonded in a linear geometry to one Nb5+ and one P5+ atom. In the second O2- site, O2- is bonded in a distorted single-bond geometry to two equivalent Tl1+ and one P5+ atom. In the third O2- site, O2- is bonded in a distorted single-bond geometry to one Nb5+ and two equivalent Tl1+ atoms. In the fourth O2- site, O2- is bonded in a distorted bent 150 degrees geometry to one Nb5+, one Tl1+, and one P5+ atom. In the fifth O2- site, O2- is bonded in a distorted bent 150 degrees geometry to one Nb5+ and one P5+ atom. In the sixth O2- site, O2- is bonded in a distorted bent 150 degrees geometry to one Nb5+ and one P5+ atom. In the seventh O2- site, O2- is bonded in a bent 150 degrees geometry to one Nb5+ and one P5+ atom. In the eighth O2- site, O2- is bonded in a 2-coordinate geometry to one Tl1+ and two P5+ atoms.