A Density Functional Investigation on LinI (n =1-8) Clusters

Abstract

A density functional theory (DFT) investigation on isomeric structures of lithium-iodide clusters, and stabilities as well as electronic structure features of global equilibrium structures are reported. The relative energies and population values of structural isomers for LinI (n = 1-8) clusters are obtained at the B3LYP/Lanl2dz and B3LYP/6-311G(d,p) theory levels. The iodine atom prefers the apex position in the most stable structures within the coordination number two except Li6I and Li8I clusters. The binding energies, dissociation energies, second-order energy differences, HOMO-LUMO gaps, ionization and elimination energies of global minimum structures are calculated in order to get beneficial information about the stability and electronic properties of LinI (n = 1-8) clusters. The results of relative energies affirm an odd-even oscillation that LinI (n = 1, 3, 5, 7) clusters are more stable than neighboring clusters. The iodine atom also enhances the stability order of pure lithium clusters while the cluster size grows up this stability decreases, and lithium-iodide clusters become more reactive. The ionization and elimination energy results also show that LinI (n = 1-8) clusters can be classified as superalkalies due to owing lower ionization energies than Li atom and the interaction between pure lithium clusters and iodine atom can be realized as electrostatic bonding.