Probing the role of excited states in ionization of acetylene. Issue 30 (21st April 2017)

• Record Type: Journal Article
• Authors: Dundas, Daniel; Mulholland, Peter; Wardlow, Abigail; de la Calle, Alejandro
• Is Part Of: Physical chemistry chemical physics. Volume 19:Issue 30(2017)
• Page Start: 19619
• Page End: 19630
• Publication Date: 2017-04-21
• Subjects: Chemistry, Physical and theoretical -- Periodicals; 541.3
• DOI: 10.1039/c7cp01661a
• Languages: English
• ISSNs: 1463-9076

Abstract

Abstract : Angularly-resolved photoelectron spectra for acetylene ionized by ultrashort laser pulses are calculated: these show how excited states influence electron emission. Abstract : Ionization of acetylene by linearly-polarized, vacuum ultraviolet (VUV) laser pulses is modelled using time-dependent density functional theory. Several laser wavelengths are considered including one that produces direct ionization to the first excited cationic state while another excites the molecules to a Rydberg series incorporating an autoionizing state. We show that for the wavelengths and intensities considered, ionization is greatest whenever the molecule is aligned along the laser polarization direction. By considering high harmonic generation we show that populating excited states can lead to a large enhancement in the harmonic yield. Lastly, angularly-resolved photoelectron spectra are calculated which show how the energy profile of the emitted electrons significantly changes in the presence of these excited states.