Theoretical Study of the Electronic Properties of Nickel Clusters

Abstract

Low-energy geometry and electronic structures of nickel (Nin) clusters, where the number of atoms n constituting these clusters ranges from 2 to 10, have been obtained based on density functional theory (DFT) with the use of Generalized Gradient Approximation (GGA) taken from SIESTA method. By searching for clusters with low-energy structures, new structures with low-energies were obtained. For each cluster size, the average bond length, binding energy, HOMO-LUMO gap, second difference in energy, Vertical Ionization Potential (VIP), adiabatic ionization potential (AIP) and finally the Density of States (DOS) were calculated by this method. Low-energy structures of clusters are even for values n ≤ 6, while stability showed that the cluster Ni10 has the highest value of the binding energy. The VIP, AIP and HOMO-LUMO gap show clear oscillations at odd and even values, indicating that Ni2,4,6,8,10 clusters have a higher stability compared to their neighboring clusters. The second difference in energy shows and confirms the stability of the aforementioned clusters. The results also show the DOS of the clusters studied near the Fermi level and the relation of oscillation behavior witnessed by odd and even clusters in the number of atoms with their stability. In this research, I succeeded in studying some clusters of nickel Nin using DFT, tackling their structural aspects as well as their electronic properties.