The $\nu_{3}$ band contour formation mechanisms in absorption and Raman spectra of tetrafluoromethane in condensed phases

In the framework of this investigation, the mechanisms forming the complex contours of the $\nu_{3}$ and $\nu_{1}+\nu_{3}$ bands of tetrafluoromethane (CF$_4$) in condensed low-temperature systems – a liquid, a plastic crystal, and a low-temperature solution in liquid Ar – were studied using absorption and Raman spectroscopy. In this study, an experimental Raman spectrum of CF$_4$ in the liquid phase was registered, which was used to obtain the parameters of rotational collapse in the liquid phase, and quantitative data on the band contours in the fundamental region of the spectrum. The main goal of the study is to determine the various mechanism contributions to the formation of the studied band contours such as resonant dipole-dipole interaction, Fermi resonance, and hindered rotation. To solve the problem, the mathematical apparatus of spectral moments was applied. As a result, it was shown that the dominant mechanism of the formation of the contours of the studied band is the resonant dipole-dipole interaction, the values of which were calculated and presented in this article.