Photoelectron imaging spectroscopy and photodynamics of m-xylene cations. (12th February 2019)

• Record Type: Journal Article
• Authors: Liu, Yuzhu; Yan, Yihui; Yin, Wenyi; Liu, Bo; Gerber, Thomas; Knopp, Gregor
• Is Part Of: Laser physics letters. Volume 16:Number 3(2019:Mar.)
• Publication Date: 2019-02-12
• Subjects: m-xylene -- cations -- multiphoton ionization -- photoelectron spectroscopy -- pump probe; Lasers -- Periodicals; Physics -- Periodicals; 621.366
• DOI: 10.1088/1612-202X/aaff52
• Languages: English
• ISSNs: 1612-2011

Abstract

Abstract: The delayed photofragmentation and photoelectron spectroscopy coupled with DFT calculations were employed for the investigation of the relaxation dynamics of m-xylene cations. The multiphoton ionization induced by the pump pulse was used for the preparation of the m-xylene cations, and the population was characterized by the technique of photoelectron imaging. A time-delayed probe pulse was used to excite the prepared m-xylene cations to energetically higher electronic states, which undergo fragmentation. The relaxation dynamics of the m-xylene cations was tracked by monitoring the depletion of excited parent-ion and the formation of the fragment-ion. Two relaxation time constants are determined by monitoring the depletion of the excited parent-ion and the formation of the fragment-ion with the delay time. The first component of τ 1 = 764 (±25) fs is attributed to an intramolecular vibrational redistribution process within the D 0 state and the slow one of τ 2 > 440 ns is ascribed to the long lifetime of the cations.