Effect of functional group (fluorine) of aromatic thiols on electron transfer at the molecule-metal interface

Wei Chen; Li Wang; Chun Huang; Ting Ting Lin; Xing Yu Gao; Kian Ping Loh; Zhi Kuan Chen; Andrew Thye Shen Wee

doi:10.1021/ja056324a

Effect of functional group (fluorine) of aromatic thiols on electron transfer at the molecule-metal interface

J Am Chem Soc. 2006 Jan 25;128(3):935-9. doi: 10.1021/ja056324a.

Authors

Wei Chen¹, Li Wang, Chun Huang, Ting Ting Lin, Xing Yu Gao, Kian Ping Loh, Zhi Kuan Chen, Andrew Thye Shen Wee

Affiliation

¹ Department of Physics, National University of Singapore, 2 Science Drive 3, Singapore 117542, Singapore.

PMID: 16417384
DOI: 10.1021/ja056324a

Abstract

Electron transfer at the molecule-metal interface of self-assembled monolayers of 1,1';4',1''-terphenyl-4''-thiol (BBB) and its partially fluorinated counterpart (BFF: p-thiophenyl-nonafluorobiphenyl) on Au(111) is investigated by core-hole clock spectroscopy. Ultrafast electron transfer at the BBB/Au(111) interface in the low-femtosecond regime (on the same time scale as the C 1s core-hole lifetime, approximately 6 fs) was observed. In contrast, for BFF/Au(111), the interface electron transfer was forbidden during the core-hole decay. This strongly suggests that fluorination of phenyl rings significantly enhances the localization of the excited electrons in the LUMO.