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arXiv · 2105.12556

The Rotationally Resolved Infrared Spectrum of TiO and Its Isotopologues

Abstract

In this study, we present the ro-vibrationally resolved gas-phase spectrum of the diatomic molecule TiO around 1000\,cm$^{-1}$. Molecules were produced in a laser ablation source by vaporizing a pure titanium sample in the atmosphere of gaseous nitrous oxide. Adiabatically expanded gas, containing TiO, formed a supersonic jet and was probed perpendicularly to its propagation by infrared radiation from quantum cascade lasers. Fundamental bands of $^{46-50}$TiO and vibrational hotbands of $^{48}$TiO are identified and analyzed. In a mass-independent fitting procedure combining the new infrared data with pure rotational and electronic transitions from the literature, a Dunham-like parameterization is obtained. From the present data set, the multi-isotopic analysis allows to determine the spin-rotation coupling constant $γ$ and the Born-Oppenheimer correction coefficient $Δ_{\rm U_{10}}^{\mathrm{Ti}}$ for the first time. The parameter set enables to calculate the Born-Oppenheimer correction coefficients $Δ_{\rm U_{02}}^{\mathrm{Ti}}$ and $Δ_{\rm U_{02}}^{\mathrm{O}}$. In addition, the vibrational transition moments for the observed vibrational transitions are reported.

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Daniel Witsch, Alexander A. Breier, Eileen Döring, Koichi M. T. Yamada, Thomas F. Giesen, Guido W. Fuchs. 2021-05-26. The Rotationally Resolved Infrared Spectrum of TiO and Its Isotopologues. https://doi.org/10.1016/j.jms.2021.111439

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