Theoretical Study of Electron Transfer and Electron Transport Processes in Molecular Systems at Metal Substrates

In this paper we present a study of electron transfer and electron transport processes in molecular systems at metal substrates. In particular, photoinduced electron transfer in molecules at metal surfaces and voltage driven electron transport in single-molecule junctions are investigated. The methodology is based on a combination of first-principle electronic structure methods to characterize the systems and dynamical basis-set as well as nonequilibrium Green's function methods to study electron transfer dynamics and transport properties, respectively. The results show the ultrafast character of electron transfer at molecule-metal interfaces and demonstrate the importance of electronic-vibrational coupling in single-molecule junctions. Furthermore, a mechanism for photoinduced switching of molecular junctions based on hydrogen translocation is discussed.