Materials Data on Sr2NbN3 by Materials Project

Sr2NbN3 crystallizes in the monoclinic C2/c space group. The structure is three-dimensional. there are two inequivalent Sr2+ sites. In the first Sr2+ site, Sr2+ is bonded to six N3- atoms to form distorted SrN6 pentagonal pyramids that share corners with two equivalent SrN6 pentagonal pyramids, corners with two equivalent NbN4 tetrahedra, edges with two equivalent SrN6 pentagonal pyramids, and edges with three equivalent NbN4 tetrahedra. There are a spread of Sr–N bond distances ranging from 2.61–2.87 Å. In the second Sr2+ site, Sr2+ is bonded in a 6-coordinate geometry to six N3- atoms. There are a spread of Sr–N bond distances ranging from 2.60–3.09 Å. Nb5+ is bonded to four N3- atoms to form NbN4 tetrahedra that share corners with two equivalent SrN6 pentagonal pyramids, corners with two equivalent NbN4 tetrahedra, and edges with three equivalent SrN6 pentagonal pyramids. There are a spread of Nb–N bond distances ranging from 1.91–2.03 Å. There are four inequivalent N3- sites. In the first N3- site, N3- is bonded to four Sr2+ and one Nb5+ atom to form distorted edge-sharing NSr4Nb trigonal bipyramids. In the second N3- site, N3- is bonded in a distorted linear geometry to four Sr2+ and two equivalent Nb5+ atoms. In the third N3- site, N3- is bonded in a 6-coordinate geometry to four Sr2+ and two equivalent Nb5+ atoms. In the fourth N3- site, N3- is bonded in a 5-coordinate geometry to four Sr2+ and one Nb5+ atom.