Bond-breaking and adsorption of molecules at plasmonic hot-spots initiated by infrared vibrational excitation

摘要

We demonstrate that metal-carbonyl compounds in liquid n-hexane are dissociated and adsorbed on gold surfaces upon vibrational excitation. We illuminate gold nanoantennas with temporally-shaped mid-infrared pulses to produce intense plasmonic near-fields. The produced near-fields induce vibrational ladder climbing and the resultant dissociation of metal-carbonyl compounds. A new band, cumulatively increase with irradiation, is attributed to the molecular species which are dissociated and adsorbed on gold surfaces. This demonstration proves that the plasmonic near-fields of mid-infrared pulses are useful for mode-selective reaction control at electronic ground states and for possible subsequent manipulation of molecules like trapping and alignment.