Materials Data on CrNi2BO5 by Materials Project

Abstract

Ni2CrO2BO3 crystallizes in the orthorhombic Pbam space group. The structure is three-dimensional. Cr3+ is bonded to six O2- atoms to form CrO6 octahedra that share corners with four NiO6 octahedra, edges with two equivalent CrO6 octahedra, and edges with five NiO6 octahedra. The corner-sharing octahedra tilt angles range from 15–62°. There are a spread of Cr–O bond distances ranging from 1.99–2.08 Å. There are three inequivalent Ni2+ sites. In the first Ni2+ site, Ni2+ is bonded to six O2- atoms to form NiO6 octahedra that share corners with two equivalent NiO6 octahedra, edges with two equivalent NiO6 octahedra, and edges with four equivalent CrO6 octahedra. The corner-sharing octahedral tilt angles are 60°. There are two shorter (2.02 Å) and four longer (2.13 Å) Ni–O bond lengths. In the second Ni2+ site, Ni2+ is bonded to six O2- atoms to form NiO6 octahedra that share a cornercorner with one NiO6 octahedra, corners with two equivalent CrO6 octahedra, edges with two equivalent CrO6 octahedra, and edges with four NiO6 octahedra. The corner-sharing octahedra tilt angles range from 60–62°. There are a spread of Ni–O bond distances ranging from 1.97–2.15 Å. In the third Ni2+ site, Ni2+ is bonded to six O2- atoms to form NiO6 octahedra that share corners with four equivalent CrO6 octahedra, edges with two equivalent CrO6 octahedra, and edges with six NiO6 octahedra. The corner-sharing octahedral tilt angles are 15°. There are two shorter (2.08 Å) and four longer (2.09 Å) Ni–O bond lengths. B3+ is bonded in a trigonal planar geometry to three O2- atoms. There are a spread of B–O bond distances ranging from 1.38–1.40 Å. There are five inequivalent O2- sites. In the first O2- site, O2- is bonded in a distorted rectangular see-saw-like geometry to one Cr3+, two equivalent Ni2+, and one B3+ atom. In the second O2- site, O2- is bonded to two equivalent Cr3+ and two Ni2+ atoms to form distorted OCr2Ni2 tetrahedra that share corners with three equivalent OCr2Ni3 square pyramids, corners with three equivalent OCr2Ni2 tetrahedra, and an edgeedge with one OCr2Ni3 square pyramid. In the third O2- site, O2- is bonded in a 4-coordinate geometry to three Ni2+ and one B3+ atom. In the fourth O2- site, O2- is bonded to two equivalent Cr3+ and three Ni2+ atoms to form OCr2Ni3 square pyramids that share corners with two equivalent OCr2Ni3 square pyramids, corners with three equivalent OCr2Ni2 tetrahedra, edges with three equivalent OCr2Ni3 square pyramids, and an edgeedge with one OCr2Ni2 tetrahedra. In the fifth O2- site, O2- is bonded in a 4-coordinate geometry to one Cr3+, two equivalent Ni2+, and one B3+ atom.