First-Principles Studies on the Structural and Electronic Properties of As Clusters

Based on the genetic algorithm (GA) incorporated with density functional theory (DFT) calculations, the structural and electronic properties of neutral and charged arsenic clusters As(n) (n = 2–24) are investigated. The size-dependent physical properties of neutral clusters, such as the binding energy, HOMO-LUMO gap, and second difference of cluster energies, are discussed. The supercluster structures based on the As(8) unit and As(2) bridge are found to be dominant for the larger cluster As(n) (n ≥ 8). Furthermore, the possible geometric structures of As(28), As(38), and As(180) are predicted based on the growth pattern.