Ultrafast imaging of electronic relaxation in n-propylbenzene: Direct observation of intermediate state

Yuzhu Liu; Thomas Gerber; Peter Radi; Gregor Knopp

doi:10.1016/j.saa.2015.04.050

Ultrafast imaging of electronic relaxation in n-propylbenzene: Direct observation of intermediate state

Spectrochim Acta A Mol Biomol Spectrosc. 2015 Oct 5:149:54-8. doi: 10.1016/j.saa.2015.04.050. Epub 2015 Apr 24.

Authors

Yuzhu Liu¹, Thomas Gerber², Peter Radi², Gregor Knopp²

Affiliations

¹ School of Physics and Optoelectronic Engineering, Nanjing University of Information Science & Technology, 210044 Nanjing, China. Electronic address: yuzhu.liu@gmail.com.
² Paul Scherrer Institute, 5232 Villigen, Switzerland.

PMID: 25942085
DOI: 10.1016/j.saa.2015.04.050

Abstract

The ultrafast dynamics of the second singlet electronically excited state (S2) in n-propylbenzene has been investigated by femtosecond time-resolved photoelectron imaging coupled with photofragmentation spectroscopy. The intermediate state for the deactivation of the S2 state is observed by transient photoelectron kinetic energy distributions and photoelectron angular distributions. An ultrafast electronic relaxation process on timescale of the fitted ∼50 fs was observed in the S2 state by time-resolved photoelectron imaging and it is attributed to the S1←S2 internal conversion (IC). The time constant of 1.23 (±0.2) ps is determined for the further deactivation of the intermediate S1 state.

Keywords: Internal conversion; Photochemical; Photoelectron imaging spectroscopy; Pump–probe; Ultrafast.

Publication types

Research Support, Non-U.S. Gov't