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تسجيل مستخدم جديدThe Rotationally Resolved Infrared Spectrum of TiO and Its Isotopologues
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Daniel Witsch
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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 $gamma$ and the Born-Oppenheimer correction coefficient $Delta_{rm U_{10}}^{mathrm{Ti}}$ for the first time. The parameter set enables to calculate the Born-Oppenheimer correction coefficients $Delta_{rm U_{02}}^{mathrm{Ti}}$ and $Delta_{rm U_{02}}^{mathrm{O}}$. In addition, the vibrational transition moments for the observed vibrational transitions are reported.
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