Ground state geometries and energetics of AL(n)Li (n=1,13) clusters using ab initio density-based molecular dynamics

Based on orbital-free ab initio molecular dynamics calculations, the geometries and energetics of lithium-doped aluminium clusters (AlnLi, n = 1, 13) have been investigated. It is seen that, a single impurity of Li affects the geometries of small (n < 6) clusters, and this effect is less pronounced for larger clusters. The results suggest extra stability for the Al3Li, Al6Li and A(13)Li clusters, which are in contrast with our earlier results on LinAl. The results indicate that the Li atom segregates to the surface of the aluminium cluster and prefers to form a tetrahedron, wherever possible, with one of the triangular faces of Al atoms. In particular, for Al13Li, the Al-13 core takes the most symmetric icosahedral form with the Li atom occupying the outer 'hollow-site'.