Structure and stability of Al13I clusters.

We have performed density functional calculations for the structures and stabilities of Al(13)I at the scalar relativistic pseudopotential and all-electron levels of theory. The Al(13) moiety in Al(13)I is significantly distorted and structurally similar to an Al(13) cation, where the natural population is -0.27e for the I atom. Unlike other Al(13)-M (M=H, alkali metals, and coinage metals) clusters, a C(s)-ontop structure was found to be the most stable form. The Al(13)I cluster has a large Al(13)-I binding energy of 3.11 eV and is more stable, as charge transfer to the electronegative I atom is larger.