Materials Data on Sr4N3 by Materials Project
Sr4N3 crystallizes in the triclinic P1 space group. The structure is three-dimensional. there are four inequivalent Sr2+ sites. In the first Sr2+ site, Sr2+ is bonded in a rectangular see-saw-like geometry to four N+2.67- atoms. There are a spread of Sr–N bond distances ranging from 2.53–2.80 Å. In the second Sr2+ site, Sr2+ is bonded to four N+2.67- atoms to form distorted SrN4 trigonal pyramids that share corners with two equivalent SrN5 square pyramids, corners with six SrN4 trigonal pyramids, edges with two equivalent SrN5 square pyramids, and an edgeedge with one SrN4 trigonal pyramid. There are a spread of Sr–N bond distances ranging from 2.38–2.71 Å. In the third Sr2+ site, Sr2+ is bonded to four N+2.67- atoms to form SrN4 trigonal pyramids that share corners with two equivalent SrN5 square pyramids, corners with six SrN4 trigonal pyramids, edges with two equivalent SrN5 square pyramids, and an edgeedge with one SrN4 trigonal pyramid. There are a spread of Sr–N bond distances ranging from 2.56–2.85 Å. In the fourth Sr2+ site, Sr2+ is bonded to five N+2.67- atoms to form distorted SrN5 square pyramids that share corners with four SrN4 trigonal pyramids, edges with two equivalent SrN5 square pyramids, and edges with four SrN4 trigonal pyramids. There are a spread of Sr–N bond distances ranging from 2.53–2.85 Å. There are three inequivalent N+2.67- sites. In the first N+2.67- site, N+2.67- is bonded to six Sr2+ atoms to form edge-sharing NSr6 octahedra. In the second N+2.67- site, N+2.67- is bonded in a 5-coordinate geometry to five Sr2+ atoms. In the third N+2.67- site, N+2.67- is bonded to six Sr2+ atoms to form distorted edge-sharing NSr6 octahedra.