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arXiv · 1508.03998

Test of quantum chemistry in vibrationally-hot hydrogen molecules

M. L. Niu·E. J. Salumbides·W. Ubachs
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Abstract

Precision measurements are performed on highly excited vibrational quantum states of molecular hydrogen. The $v=12, J=0-3$ rovibrational levels of H$_2$ ($X^1Σ_g^+$), lying only $2000$ cm$^{-1}$ below the first dissociation limit, were populated by photodissociation of H$_2$S and their level energies were accurately determined by two-photon Doppler-free spectroscopy. A comparison between the experimental results on $v=12$ level energies with the best \textit{ab initio} calculations shows good agreement, where the present experimental accuracy of $3.5 \times10^{-3}$ cm$^{-1}$ is more precise than theory, hence providing a gateway to further test theoretical advances in this benchmark quantum system.

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M. L. Niu, E. J. Salumbides, W. Ubachs. 2015-08-17. Test of quantum chemistry in vibrationally-hot hydrogen molecules. https://doi.org/10.1063/1.4929568

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