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arXiv · 2010.08849

Ab initio relativistic treatment of the intercombination $a^3\Pi-X^1\Sigma^+$ Cameron system of the CO molecule

Nikolai S. Mosyagin·Alexander V. Oleynichenko·Andrei Zaitsevskii·Artur V. Kudrin·Elena A. Pazyuk·Andrey V. Stolyarov
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Abstract

The intercombination $a^3\Pi - X^1\Sigma^+$ Cameron system of carbon monoxide has been computationally studied in the framework of multi-reference Fock space coupled cluster method with the use of generalized relativistic pseudopotential model for the effective introducing the relativity in all-electron correlation treatment. The extremely weak $a^3\Pi_{\Omega=0^+,1} - X^1\Sigma^+$ transition probabilities and radiative lifetimes of the metastable $a^3\Pi$ state were calculated and compared with their previous theoretical and experimental counterparts. The impact of a presumable variation of the fine structure constant $\alpha=e^2/\hbar c$ on transition strength of the Cameron system has been numerically evaluated as well.

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Nikolai S. Mosyagin, Alexander V. Oleynichenko, Andrei Zaitsevskii, Artur V. Kudrin, Elena A. Pazyuk, Andrey V. Stolyarov. 2020-10-17. Ab initio relativistic treatment of the intercombination $a^3\Pi-X^1\Sigma^+$ Cameron system of the CO molecule. https://doi.org/10.1016/j.jqsrt.2021.107532

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