Elucidation of the Spin-Orbit and Relativistic Effects on the Plasmon Excitations of Silver and Gold Nanowire: Time-Dependent Density Functional Theory

The excitation spectra of linear atomic silver and gold with various sizes have been calculatedusing time-dependent density functional theory. Our results show strong resonances for the pure Agnanoparticles and strongly broadened spectra with many transitions for the pure gold structures. Moreover,the resonance energies are strongly dependent on the size of the nano wire. Gold and silver show acontinuously decreasing resonance energy with increasing length. Spin orbit interaction does not havea considerable effect on orbital energy and hybridization of orbitals in Ag chain, but for gold chain, it is ofparticular importance. Without considering the relativity, the electronic spectra of Ag8 and Au8 have thesame scheme.

Keywords:

plasmon , noble metals , optical properties , nanowire , spin-orbit