University of Illinois Urbana-Champaign

Demonstration Of Cresu-rempi For Reaction Kinetic Measurements In The Gas-phase

Gurusinghe, Ranil

Content Files
WJ04_1.pptx
6277.pdf

Permalink

https://hdl.handle.net/2142/116743

Description

Title
Demonstration Of Cresu-rempi For Reaction Kinetic Measurements In The Gas-phase
Author(s)
Gurusinghe, Ranil
Contributor(s)
  • Suits, Arthur
  • Edlin, Matthew L.
  • Lang, Jinxin
  • Dias, Nureshan
Issue Date
2022-06-22
Keyword(s)
Instrument/Technique Demonstration
Abstract
The CRESU technique (French acronym for “reaction kinetics in uniform supersonic flows”) provides a wall-less gas-phase reactor to measure low-temperature reaction kinetics. In the past, probing methods such as laser-induced fluorescence (LIF), mass spectrometry, and chirped-pulse uniform flow (CPUF) microwave spectroscopy have been successfully used to measures reaction kinetics in CRESU flows, but the latter two call for sampling of the flow prior to detection. Here we show a selective, low-cost, and highly sensitive probing tool to measure the kinetics of reactions that involve both molecular and atomic species. This new detection method uses resonance-enhance multi-photon ionization (REMPI) and an electron capture probe, adapted from approaches successfully used in flames, to selectively identify atomic and molecular species. A negative-biased high voltage applied to two electrodes, that are placed on either side of a grounded probe, enables rapid capture of electrons produced by the selective ionization from the REMPI spectroscopy. The performance of this setup was verified by recording the (1+1) REMPI spectra of nitric oxide in 20 K and 50 K uniform supersonic flows. The REMPI probe response is proportional to the number of electrons produced by ionization, and therefore to the concentration of ionized species. Thus, the time-dependent REMPI signal can be used to measure the rate of decay or growth of a reactant or product in fast chemical reactions in CRESU flows.
Publisher
International Symposium on Molecular Spectroscopy
Type of Resource
text
Genre of Resource
Conference Paper / Presentation
Language
eng
Handle URL
https://hdl.handle.net/2142/116743
DOI
https://doi.org/10.15278/isms.2022.WJ04
Copyright and License Information
Copyright 2022 held by the authors

Owning Collections

Abstracts & Presentations - 2022 International Symposium on Molecular Spectroscopy PRIMARY