Materials Data on Ge3N4 by Materials Project

Abstract

Ge3N4 is Hausmannite-like structured and crystallizes in the orthorhombic Pnma space group. The structure is three-dimensional. there are three inequivalent Ge4+ sites. In the first Ge4+ site, Ge4+ is bonded to four N3- atoms to form a mixture of distorted edge and corner-sharing GeN4 trigonal pyramids. The corner-sharing octahedra tilt angles range from 64–68°. There are a spread of Ge–N bond distances ranging from 1.82–1.91 Å. In the second Ge4+ site, Ge4+ is bonded to six N3- atoms to form distorted GeN6 octahedra that share corners with eight GeN6 octahedra, corners with four equivalent GeN4 trigonal pyramids, edges with two equivalent GeN6 octahedra, and an edgeedge with one GeN4 trigonal pyramid. The corner-sharing octahedra tilt angles range from 49–55°. There are a spread of Ge–N bond distances ranging from 1.98–2.30 Å. In the third Ge4+ site, Ge4+ is bonded to six N3- atoms to form GeN6 octahedra that share corners with four equivalent GeN6 octahedra, corners with two equivalent GeN4 trigonal pyramids, edges with four GeN6 octahedra, and edges with two equivalent GeN4 trigonal pyramids. The corner-sharing octahedra tilt angles range from 50–55°. There are two shorter (1.97 Å) and four longer (2.07 Å) Ge–N bond lengths. There are three inequivalent N3- sites. In the first N3- site, N3- is bonded to four Ge4+ atoms to form corner-sharing NGe4 tetrahedra. In the second N3- site, N3- is bonded in a rectangular see-saw-like geometry to four Ge4+ atoms. In the third N3- site, N3- is bonded in a rectangular see-saw-like geometry to four Ge4+ atoms.