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arXiv · 1609.06053

Tunnelling splitting in the phosphine molecule

Clara Sousa-Silva·Jonathan Tennyson·Sergey N. Yurchenko
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Abstract

Splitting due to tunnelling via the potential energy barrier has played a significant role in the study of molecular spectra since the early days of spectroscopy. The observation of the ammonia doublet led to attempts to find a phosphine analogous, but these have so far failed due to its considerably higher barrier. Full dimensional, variational nuclear motion calculations are used to predict splittings as a function of excitation energy. Simulated spectra suggest that such splittings should be observable in the near infrared via overtones of the $ν_2$ bending mode starting with $4ν_2$.

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Clara Sousa-Silva, Jonathan Tennyson, Sergey N. Yurchenko. 2016-09-20. Tunnelling splitting in the phosphine molecule. https://doi.org/10.1063/1.4962259

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