Materials Data on CrNiPO5 by Materials Project

Abstract

NiCr(PO4)O crystallizes in the monoclinic C2/c space group. The structure is three-dimensional. Cr3+ is bonded to six O2- atoms to form CrO6 octahedra that share corners with two equivalent CrO6 octahedra, corners with two equivalent NiO6 octahedra, corners with four equivalent PO4 tetrahedra, and faces with two equivalent NiO6 octahedra. The corner-sharing octahedra tilt angles range from 52–56°. There are a spread of Cr–O bond distances ranging from 2.01–2.04 Å. Ni2+ is bonded to six O2- atoms to form NiO6 octahedra that share corners with two equivalent CrO6 octahedra, corners with two equivalent NiO6 octahedra, corners with four equivalent PO4 tetrahedra, and faces with two equivalent CrO6 octahedra. The corner-sharing octahedra tilt angles range from 56–59°. There are four shorter (2.07 Å) and two longer (2.11 Å) Ni–O bond lengths. P5+ is bonded to four O2- atoms to form PO4 tetrahedra that share corners with four equivalent CrO6 octahedra and corners with four equivalent NiO6 octahedra. The corner-sharing octahedra tilt angles range from 39–43°. There is two shorter (1.54 Å) and two longer (1.55 Å) P–O bond length. There are three inequivalent O2- sites. In the first O2- site, O2- is bonded in a 3-coordinate geometry to one Cr3+, one Ni2+, and one P5+ atom. In the second O2- site, O2- is bonded in a 3-coordinate geometry to one Cr3+, one Ni2+, and one P5+ atom. In the third O2- site, O2- is bonded in a 4-coordinate geometry to two equivalent Cr3+ and two equivalent Ni2+ atoms.