Filled and empty states of alkanethiol monolayer on Au (1Â 1Â 1): Fermi level asymmetry and implications for electron transport

► Alkanethiol SAMs on Au are investigated via UPS and IPES measurements. ► The metal Fermi level is significantly closer to the LUMO than to their HOMO. ► The results suggest that charge carrier tunneling is controlled by the LUMO.