Infrared Spectroscopy of CH<sub>5</sub><sup>+</sup> Cations in Helium Nanodroplets
The methanium CH<sub>5</sub><sup>+</sup> is a prototypical fluxional ion whose infrared spectra remain unassigned. Here we report on the infrared spectra of CH<sub>5</sub><sup>+</sup> cations and its deuterated isotopomer, CH<sub>4</sub>D<sup>+</sup>, in helium droplets at a low temperature of 0.38 K. The ions were produced upon protonation of CH<sub>4</sub> molecules, a technique that was developed in this work. The spectra of CH<sub>5</sub><sup>+</sup> around 3000 cm<sup>-1</sup> show two strong and broad infrared bands and a weak shoulder, reflecting its highly fluxional nature. The spectrum of CH<sub>4</sub>D<sup>+</sup> shows a much sharper infrared band, indicating a partial quenching of the exchange of H/D atoms. This work also reports on the infrared spectrum of the methane dimer radical cations (CH<sub>4</sub>)<sub>2</sub><sup>+</sup>.
Authors
- Andrey F. Vilesov (ORCID: https://orcid.org/0000-0002-8412-817X)
- Amandeep Singh (ORCID: https://orcid.org/0000-0003-1568-2043)
- Deepak Verma (ORCID: https://orcid.org/0000-0001-8265-1453)
- Andrew Abishek A. Azhagesan (ORCID: https://orcid.org/0009-0004-2251-1749)
- S Allison
Institutions
- University of Southern California (US)
- Mount St. Mary's University (US)
Publication Details
- Journal
- The Journal of Physical Chemistry Letters
- Published
- 2024-10-24
- DOI
- https://doi.org/10.1021/acs.jpclett.4c02614
- Citations
- 5
- Primary Topic
- Quantum, superfluid, helium dynamics
- Type
- article
- Field-Weighted Citation Impact
- 1.69
Funders
- Division of Chemistry