Effect of functional group (fluorine) of aromatic thiols on electron transfer at the molecule-metal interface.
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.
Chen
Wei
W
Department of Physics, National University of Singapore, 2 Science Drive 3, Singapore 117542, Singapore.
Wang
Li
L
Huang
Chun
C
Lin
Ting Ting
TT
Gao
Xing Yu
XY
Loh
Kian Ping
KP
Chen
Zhi Kuan
ZK
Wee
Andrew Thye Shen
AT