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arXiv · 2012.00374

A new instrument for kinetics and branching ratio studies of gas phase collisional processes at very low temperatures

Olivier Durif·Michael Capron·Joey P. Messinger·Abdessamad Benidar·Ludovic Biennier·Jérémy Bourgalais·André Canosa·Jonathan Courbe·Gustavo A. Garcia·Jean-François Gil·Laurent Nahon·Mitchio Okumura·Lucile Rutkowski·Ian R. Sims·Jonathan Thiévin·Sébastien D. Le Picard
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Abstract

A new instrument dedicated to the kinetic study of low-temperature gas phase neutral-neutral reactions, including clustering processes, is presented. It combines a supersonic flow reactor with Vacuum Ultra-Violet (VUV) synchrotron photoionization time of flight mass spectrometry. A photoion-photoelectron coincidence detection scheme has been adopted to optimize the particle counting efficiency. The characteristics of the instrument are detailed along with its capabilities illustrated through a few results obtained at low temperatures (< 100 K) including a {photoionization spectrum} of n-butane, the detection of formic acid dimer formation as well as the observation of diacetylene molecules formed by the reaction between the C$_2$H radical and C$_2$H$_2$.

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Olivier Durif, Michael Capron, Joey P. Messinger, Abdessamad Benidar, Ludovic Biennier, Jérémy Bourgalais, André Canosa, Jonathan Courbe, Gustavo A. Garcia, Jean-François Gil, Laurent Nahon, Mitchio Okumura, Lucile Rutkowski, Ian R. Sims, Jonathan Thiévin, Sébastien D. Le Picard. 2020-12-01. A new instrument for kinetics and branching ratio studies of gas phase collisional processes at very low temperatures. https://doi.org/10.1063/5.0029991

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