Materials Data on Sr4ZrN4 by Materials Project

Abstract

Sr4ZrN4 crystallizes in the triclinic P-1 space group. The structure is three-dimensional. there are four inequivalent Sr2+ sites. In the first Sr2+ site, Sr2+ is bonded in a distorted rectangular see-saw-like geometry to four N3- atoms. There are a spread of Sr–N bond distances ranging from 2.57–2.68 Å. In the second Sr2+ site, Sr2+ is bonded to four N3- atoms to form distorted SrN4 trigonal pyramids that share corners with four SrN5 square pyramids, corners with four equivalent ZrN4 tetrahedra, and edges with two equivalent SrN4 trigonal pyramids. There are a spread of Sr–N bond distances ranging from 2.56–2.68 Å. In the third Sr2+ site, Sr2+ is bonded to five N3- atoms to form SrN5 square pyramids that share corners with three equivalent SrN5 square pyramids, corners with three equivalent ZrN4 tetrahedra, corners with two equivalent SrN4 trigonal pyramids, edges with five SrN5 square pyramids, and an edgeedge with one ZrN4 tetrahedra. There are a spread of Sr–N bond distances ranging from 2.66–2.73 Å. In the fourth Sr2+ site, Sr2+ is bonded to five N3- atoms to form SrN5 square pyramids that share corners with three equivalent SrN5 square pyramids, a cornercorner with one ZrN4 tetrahedra, corners with two equivalent SrN4 trigonal pyramids, edges with five SrN5 square pyramids, and edges with two equivalent ZrN4 tetrahedra. There are a spread of Sr–N bond distances ranging from 2.67–2.80 Å. Zr4+ is bonded to four N3- atoms to form ZrN4 tetrahedra that share corners with four SrN5 square pyramids, corners with four equivalent SrN4 trigonal pyramids, and edges with three SrN5 square pyramids. There are a spread of Zr–N bond distances ranging from 2.10–2.15 Å. There are four inequivalent N3- sites. In the first N3- site, N3- is bonded to five Sr2+ and one Zr4+ atom to form NSr5Zr octahedra that share corners with four NSr5Zr octahedra, corners with two equivalent NSr3Zr trigonal pyramids, and edges with eight NSr5Zr octahedra. The corner-sharing octahedra tilt angles range from 8–20°. In the second N3- site, N3- is bonded to three Sr2+ and one Zr4+ atom to form distorted NSr3Zr trigonal pyramids that share corners with ten NSr5Zr octahedra and an edgeedge with one NSr3Zr trigonal pyramid. The corner-sharing octahedra tilt angles range from 55–74°. In the third N3- site, N3- is bonded to five Sr2+ and one Zr4+ atom to form NSr5Zr octahedra that share corners with two equivalent NSr5Zr octahedra, corners with six equivalent NSr3Zr trigonal pyramids, and edges with six NSr5Zr octahedra. The corner-sharing octahedra tilt angles range from 11–12°. In the fourth N3- site, N3- is bonded to five Sr2+ and one Zr4+ atom to form distorted NSr5Zr octahedra that share corners with two equivalent NSr5Zr octahedra, corners with two equivalent NSr3Zr trigonal pyramids, and edges with nine NSr5Zr octahedra. The corner-sharing octahedra tilt angles range from 8–20°.