Calculated electronic structure of icosahedral Al and Al-Mn alloys

Electronic structure calculations on Al and Al-Mn clusters of icosahedral (Iₕ) symmetry show important differences compared with such calculations on clusters of cubic (Oₕ) symmetry. Anomalously high state densities at EF and energy dependence proportional to Eⁿ, n{≥}1, characterize the Iₕ clusters. Highly symmetric molecular-orbital topologies make icosahedral clusters appear like large quasiatoms. Central Mn atoms destabilize Iₕ clusters.