Energetics and structures of aluminum-lithium clusters

Energetics and structures of small aluminum-lithium clusters were investigated using structure-minimization and dynamic simulated annealing on the electronic Born-Oppenheimer surface, calculated via the local-spin-density-functional method in conjunction with nonlocal pseudopotentials. It is suggested that evolutionary patterns of electronic structure, energetics, and binding in AlLiₙ clusters may be analyzed within a framework where atomic-based characteristics, associated mainly with closing of the Al 3p shell, dominate for n{≤}5, while a perturbed delocalized electronic cluster-shell pattern, containing an AlLi₅ ``core,'' develops for larger clusters (i.e., for n{≥}6). The ground-state electronic and geometrical structures of AlLiₙ clusters, as well as those of Al₂{Li}₁₀$ which may be viewed as two slightly distorted ${AlLi}₅$ units bonded to each other, are discussed.