Structures Evolution, Stabilities And Electronic Properties Of MAu_n(M=Al,Si,P,S,Cl,Al;n=2-8) Clusters

Gold is an element whose unique properties are strongly influenced by relativistic effects. Gold clusters constitute an interesting research field owing to their potential applications in nanoscience because of their unique catalytic, electronic, and optical properties.We have carried out a first-principles investigation with the density functional theory (DFT) at the PBE/LANL2DZ level to systematically study the geometrical structures, growth-pattern behaviours, relative stabilities, and electronic properties of the 3p electrons atoms doped gold cluster:It is found that Al and Si prefer to occupy the center position in the most-stable MAun clusters, while P and S favor the side position. ClAun clusters can be viewed as Cl atom substituting the apex Au atom of the Aun+1 clusters. Ar atom with the full shell electrons does not substantially change the structures of the bare Aun clusters. The results indicate that the geometries of impurity-atom-doped Au clusters can be widely different due to the nature of bonding between the different dopant atom and the gold clusters. The relative stabilities of MAun clusters for the ground-state structures are analysed based on the binding energies and second-order difference of energies. It is found that partially filled 3p electrons impurities can enhance the stabilities of gold clusters. Especially, the SiAu4 cluster with Td symmetry has been found to show extraordinary stability among these clusters. Moreover, SiAu4 also exhibits kinetic stability stable with large HOMO-LUMO gap of 2.17 eV, in agreement with the available experiment. Subsequently, vertical ionization potential, vertical electron affinity, and charge transfers of these clusters have been analyzed further.