Adsorption and switching properties of a N-benzylideneaniline based molecular switch on a Au(111) surface

作者：Ovari Laszlo; Luo Ying; Leyssner Felix; Haag Rainer; Wolf Martin; Tegeder Petra^*

来源：Journal of Chemical Physics, 2010, 133(4): 044707.

DOI：10.1063/1.3460647

High resolution electron energy loss spectroscopy has been employed to analyze the adsorption geometry and the photoisomerization ability of the molecular switch carboxy-benzylideneaniline (CBA) adsorbed on Au(111). CBA on Au(111) adopts a planar (trans) configuration in the first monolayer (ML) as well as for higher coverages (up to 6 ML), in contrast to the strongly nonplanar geometry of the molecule in solution. Illumination with UV light of CBA in direct contact with the Au(111), surface (<= 1 ML) caused no changes in the vibrational structure, whereas at higher coverages (>1 ML) pronounced modifications of vibrational features were observed, which we assign to a trans -> cis isomerization. Thermal activation induced the back reaction to trans-CBA. We propose that the photoisomerization is driven by a direct (intramolecular) electronic excitation of the adsorbed CBA molecules in the second ML (and above) analogous to CBA in the liquid phase.

• 出版日期2010-7-28