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arXiv · 1206.1304

Ab initio potential curves for the X $^2Σ_u^+$, A $^2Π_u$ and B $^2Σ_g^+$ states of Ca$_{2}^+$

Sandipan Banerjee·John A. Montgomery Jr.·Jason N. Byrd·H. Harvey Michels·Robin Côté
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Abstract

We report \textit{ab initio} calculations of the X $^2 Σ_{u}^+$, A $^2Π_u$ and B $^2 Σ_{g}^+$ states of the Ca$_{2}^+$ dimer. All electron CAS+MRCI calculations are performed for the X $^2 Σ_{u}^+$ and B $^2 Σ_{g}^+$ states, while valence CAS+MRCI calculations using an effective core potential are used to describe the A $^2Π_u$ state. A double well is found in the B $^2 Σ_{g}^+$ state. Spectroscopic constants, vibrational levels, transition moments and radiative lifetimes are calculated for the most abundant isotope of calcium ($^{40}$Ca). The static dipole and quadrupole polarizabilities, and the leading order van der Waals coefficients are also calculated for all three states.

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Sandipan Banerjee, John A. Montgomery Jr., Jason N. Byrd, H. Harvey Michels, Robin Côté. 2014-07-23. Ab initio potential curves for the X $^2Σ_u^+$, A $^2Π_u$ and B $^2Σ_g^+$ states of Ca$_{2}^+$. https://doi.org/10.1016/j.cplett.2012.06.011

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