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arXiv · 2103.00957

Rovibrational spectroscopy of the CH$^+$-He and CH$^+$-He$_4$ complexes

Thomas Salomon·José L. Doménech·Philipp C. Schmid·Ernest A. Michael·Stephan Schlemmer·Oskar Asvany
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Abstract

A cryogenic 22-pole ion trap apparatus is used in combination with a table-top pulsed IR source to probe weakly bound CH$^+$-He and CH$^+$-He$_4$ complexes by predissociation spectroscopy at 4 K. The infrared photodissociation spectra of the C-H stretching vibrations are recorded in the range of 2720-2800 cm$^{-1}$. The spectrum of CH$^+$-He exhibits perpendicular transitions of a near prolate top with a band origin at 2745.9 cm$^{-1}$, and thus confirms it to have a T-shaped structure. For CH$^+$-He$_4$, the C-H stretch along the symmetry axis of this oblate top results in parallel transitions.

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Thomas Salomon, José L. Doménech, Philipp C. Schmid, Ernest A. Michael, Stephan Schlemmer, Oskar Asvany. 2021-03-01. Rovibrational spectroscopy of the CH$^+$-He and CH$^+$-He$_4$ complexes. https://doi.org/10.1016/j.jms.2021.111421

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