Materials Data on Li2AlCoO4 by Materials Project

Abstract

Li2CoAlO4 is Stannite-like structured and crystallizes in the orthorhombic Pnma space group. The structure is three-dimensional. Li1+ is bonded to four O2- atoms to form LiO4 tetrahedra that share corners with two equivalent LiO4 tetrahedra, corners with four equivalent CoO4 tetrahedra, corners with four equivalent AlO4 tetrahedra, and an edgeedge with one LiO4 tetrahedra. There are a spread of Li–O bond distances ranging from 1.96–2.04 Å. Co3+ is bonded to four O2- atoms to form CoO4 tetrahedra that share corners with four equivalent AlO4 tetrahedra and corners with eight equivalent LiO4 tetrahedra. There is two shorter (1.87 Å) and two longer (1.90 Å) Co–O bond length. Al3+ is bonded to four O2- atoms to form AlO4 tetrahedra that share corners with four equivalent CoO4 tetrahedra and corners with eight equivalent LiO4 tetrahedra. All Al–O bond lengths are 1.79 Å. There are three inequivalent O2- sites. In the first O2- site, O2- is bonded to two equivalent Li1+, one Co3+, and one Al3+ atom to form a mixture of distorted corner and edge-sharing OLi2AlCo tetrahedra. In the second O2- site, O2- is bonded to two equivalent Li1+, one Co3+, and one Al3+ atom to form corner-sharing OLi2AlCo tetrahedra. In the third O2- site, O2- is bonded to two equivalent Li1+, one Co3+, and one Al3+ atom to form corner-sharing OLi2AlCo tetrahedra.