Charge-transfer dynamics in azobenzene alkanethiolate self-assembled monolayers on gold

SURFACE SCIENCE

卷:643

Article

Gahl, Cornelius¹  Schmidt, Roland¹  Brete, Daniel¹  Paarmann, Stephanie¹  Weinelt, Martin¹ 

[1] Free Univ Berlin, Fachbereich Phys, D-14195 Berlin, Germany

关键词: Self-assembled monolayers;    Charge transfer;    Core-hole clock;    Time-resolved photoemission;    Molecular switches;   

DOI  :  10.1016/j.susc.2015.08.028

来源: Elsevier

【 摘 要 】

We have studied the charge-transfer dynamics in azobenzene-functionalized alkanethiolate self-assembled monolayers. We compare the core-hole-clock technique, i.e., resonant vs. non-resonant contributions in the azobenzene autoionization of the Cls-pi* core exciton, with the lifetime of a molecular resonance determined by two-photon photoemission spectroscopy using femtosecond laser pulses. Both techniques yield comparable charge-transfer times of 80 +/- 20 fs for a linker consisting of three CH2 groups and one oxygen unit. Thus the quenching of the excitation is about one order of magnitude faster than the time required for the trans to cis isomerization of the azobenzene photoswitch in solution. (C) 2015 Elsevier B.V. All rights reserved.

【 授权许可】

Free