ELECTRONIC-STRUCTURE OF NEGATIVELY CHARGED ALUMINUM CLUSTERS

The jellium model and density functional theory have been used to calculate the electron affinity of Al clusters as a function of size, as well as the relative stabilities of Al cluster anions. These quantities present drastic changes when a cluster electronic shell becomes filled. This is in agreement with experimental measurements by several authors. However, the jellium approximation leads to an overestimation of the oscillations of the electron affinity as a function of size. One of the key ingredients in our calculation is the use of the weighed density approximation for exchange and correlation effects. This is needed for a proper description of negatively charged clusters.