Materials Data on VNiP2O9 by Materials Project

Abstract

VNiP2O9 crystallizes in the orthorhombic Pnma space group. The structure is three-dimensional. V5+ is bonded to six O2- atoms to form distorted VO6 octahedra that share corners with two equivalent NiO6 octahedra, corners with three equivalent PO4 tetrahedra, and an edgeedge with one PO4 tetrahedra. The corner-sharing octahedral tilt angles are 47°. There are a spread of V–O bond distances ranging from 1.70–2.15 Å. Ni3+ is bonded to six O2- atoms to form NiO6 octahedra that share corners with two equivalent VO6 octahedra, corners with four PO4 tetrahedra, and edges with two equivalent NiO6 octahedra. The corner-sharing octahedral tilt angles are 47°. There are a spread of Ni–O bond distances ranging from 1.99–2.15 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 NiO6 octahedra and corners with three equivalent VO6 octahedra. The corner-sharing octahedra tilt angles range from 1–51°. There is two shorter (1.54 Å) and two longer (1.55 Å) P–O bond length. In the second P5+ site, P5+ is bonded to four O2- atoms to form PO4 tetrahedra that share corners with two equivalent NiO6 octahedra and an edgeedge with one VO6 octahedra. The corner-sharing octahedral tilt angles are 51°. There are a spread of P–O bond distances ranging from 1.53–1.59 Å. There are seven inequivalent O2- sites. In the first O2- site, O2- is bonded in a water-like geometry to one V5+ and one P5+ atom. In the second O2- site, O2- is bonded in a bent 150 degrees geometry to one V5+ and one P5+ atom. In the third O2- site, O2- is bonded in a distorted L-shaped geometry to one V5+ and one P5+ atom. In the fourth O2- site, O2- is bonded in a distorted bent 120 degrees geometry to one Ni3+ and one P5+ atom. In the fifth O2- site, O2- is bonded in a linear geometry to one V5+ and one P5+ atom. In the sixth O2- site, O2- is bonded in a distorted trigonal planar geometry to two equivalent Ni3+ and one P5+ atom. In the seventh O2- site, O2- is bonded in a 1-coordinate geometry to one V5+ and two equivalent Ni3+ atoms.