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Updated: Mar 6, 2026

Infrared Degenerate Four-wave Mixing with Upconversion Detection for Quantitative Gas Sensing
Published on: March 22, 2019
The High Resolution Infrared Spectrum of HCl
J L Doménech1, B J Drouin2, J Cernicharo3
1Molecular Physics Department, Instituto de Estructura de la Materia (IEM-CSIC), Serrano 123. E-28006 Madrid, Spain.
Abstract:
The chloroniumyl cation, HCl+, has been recently identified in space from Herschel's spectra. A joint analysis of extensive vis-UV spectroscopy emission data together with a few high-resolution and high-accuracy millimiter-wave data provided the necessary rest frequencies to support the astronomical identification. Nevertheless, the analysis did not include any infrared (IR) vibration-rotation data. Furthermore, with the end of the Herschel mission, infrared observations from the ground may be one of the few available means to further study this ion in space. In this work, we provide a set of accurate rovibrational transition wavenumbers as well as a new and improved global fit of vis-UV, IR and millimiter-wave spectroscopy laboratory data, that will aid in future studies of this molecule.
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