Materials Data on NaCaN3 by Materials Project

Abstract

NaCaN3 is Ilmenite-like structured and crystallizes in the orthorhombic Fddd space group. The structure is three-dimensional. Na1+ is bonded to six N1- atoms to form NaN6 octahedra that share corners with four equivalent CaN6 octahedra, edges with three equivalent NaN6 octahedra, and edges with four equivalent CaN6 octahedra. The corner-sharing octahedra tilt angles range from 9–40°. There are a spread of Na–N bond distances ranging from 2.48–2.55 Å. Ca2+ is bonded to six N1- atoms to form CaN6 octahedra that share corners with four equivalent NaN6 octahedra, edges with three equivalent CaN6 octahedra, and edges with four equivalent NaN6 octahedra. The corner-sharing octahedra tilt angles range from 9–40°. All Ca–N bond lengths are 2.45 Å. There are two inequivalent N1- sites. In the first N1- site, N1- is bonded to two equivalent Na1+ and two equivalent Ca2+ atoms to form a mixture of distorted edge and corner-sharing NNa2Ca2 trigonal pyramids. In the second N1- site, N1- is bonded in a rectangular see-saw-like geometry to two equivalent Na1+ and two equivalent Ca2+ atoms.