Adsorption and switching properties of a N-benzylideneaniline based molecular switch on a Au(111) surface.
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 (<or=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.
Ovári
László
L
Reaction Kinetics Research Laboratory, Institute of Nanochemistry and Catalysis, Chemical Research Center of the Hungarian Academy of Sciences, H-6720 Szeged, Dóm tér 7, Hungary.
Luo
Ying
Y
Leyssner
Felix
F
Haag
Rainer
R
Wolf
Martin
M
Tegeder
Petra
P
D000327:Adsorption; D000814:Aniline Compounds / Q000737:chemistry*; D001565:Benzoates / Q000737:chemistry*; D001597:Benzylidene Compounds / Q000737:chemistry*; D002412:Cations / Q000737:chemistry; D004583:Electrons; D004735:Energy Transfer; D006046:Gold / Q000737:chemistry*; D007536:Isomerism; D010777:Photochemistry; D012997:Solvents / Q000737:chemistry; D013057:Spectrum Analysis; D013499:Surface Properties; D013696:Temperature; D014466:Ultraviolet Rays; D014732:Vibration
C553727:4-carboxybenzylideneaniline; D000814:Aniline Compounds; D001565:Benzoates; D001597:Benzylidene Compounds; D002412:Cations; D012997:Solvents; D006046:Gold