Materials Data on Na2LiAlP2 by Materials Project

Abstract

Na2LiAlP2 crystallizes in the orthorhombic Cmce space group. The structure is three-dimensional. there are two inequivalent Na1+ sites. In the first Na1+ site, Na1+ is bonded in a 5-coordinate geometry to five P3- atoms. There are a spread of Na–P bond distances ranging from 2.96–3.10 Å. In the second Na1+ site, Na1+ is bonded to five P3- atoms to form distorted NaP5 trigonal bipyramids that share corners with six equivalent LiP4 tetrahedra, corners with six equivalent AlP4 tetrahedra, corners with four equivalent NaP5 trigonal bipyramids, edges with two equivalent LiP4 tetrahedra, edges with two equivalent AlP4 tetrahedra, and edges with two equivalent NaP5 trigonal bipyramids. There are a spread of Na–P bond distances ranging from 2.97–3.09 Å. Li1+ is bonded to four P3- atoms to form LiP4 tetrahedra that share corners with two equivalent LiP4 tetrahedra, corners with two equivalent AlP4 tetrahedra, corners with six equivalent NaP5 trigonal bipyramids, an edgeedge with one LiP4 tetrahedra, edges with three equivalent AlP4 tetrahedra, and edges with two equivalent NaP5 trigonal bipyramids. There are two shorter (2.52 Å) and two longer (2.58 Å) Li–P bond lengths. Al3+ is bonded to four P3- atoms to form AlP4 tetrahedra that share corners with two equivalent LiP4 tetrahedra, corners with two equivalent AlP4 tetrahedra, corners with six equivalent NaP5 trigonal bipyramids, an edgeedge with one AlP4 tetrahedra, edges with three equivalent LiP4 tetrahedra, and edges with two equivalent NaP5 trigonal bipyramids. There are two shorter (2.41 Å) and two longer (2.44 Å) Al–P bond lengths. There are two inequivalent P3- sites. In the first P3- site, P3- is bonded in a 9-coordinate geometry to five Na1+, two equivalent Li1+, and two equivalent Al3+ atoms. In the second P3- site, P3- is bonded in a 9-coordinate geometry to five Na1+, two equivalent Li1+, and two equivalent Al3+ atoms.