Materials Data on MgNiAsO5 by Materials Project

Abstract

MgNiAsO5 crystallizes in the orthorhombic P2_12_12_1 space group. The structure is three-dimensional. Mg2+ is bonded in a 4-coordinate geometry to five O2- atoms. There are a spread of Mg–O bond distances ranging from 2.01–2.61 Å. Ni3+ is bonded to six O2- atoms to form NiO6 octahedra that share corners with four equivalent AsO4 tetrahedra and edges with two equivalent NiO6 octahedra. There are a spread of Ni–O bond distances ranging from 1.85–2.02 Å. As5+ is bonded to four O2- atoms to form AsO4 tetrahedra that share corners with four equivalent NiO6 octahedra. The corner-sharing octahedra tilt angles range from 38–64°. There are a spread of As–O bond distances ranging from 1.70–1.73 Å. There are five inequivalent O2- sites. In the first O2- site, O2- is bonded in a 3-coordinate geometry to two equivalent Ni3+ and one As5+ atom. In the second O2- site, O2- is bonded in a water-like geometry to one Mg2+ and one As5+ atom. In the third O2- site, O2- is bonded in a distorted trigonal planar geometry to one Mg2+, one Ni3+, and one As5+ atom. In the fourth O2- site, O2- is bonded in a 4-coordinate geometry to two equivalent Mg2+, one Ni3+, and one As5+ atom. In the fifth O2- site, O2- is bonded in a trigonal non-coplanar geometry to one Mg2+ and two equivalent Ni3+ atoms.