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arXiv · 1903.06051

Explicitly correlated wavefunctions of the ground state and the lowest quintuplet state of the carbon atom

Krzysztof Strasburger
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Abstract

Variational, nonrelativisitic energies have been calculated for the ground state ($^3P_g$) and the lowest quintuplet state ($^5S_u$) of the carbon atom, with wavefunctions expressed in the basis of symmetry-projected, explicitly correlated Gaussian (ECG) lobe functions. New exact limits of these energies have been estimated, amounting to $-37.844906(4)$ and $-37.691751(2)$ hartree. With finite nuclear masses and leading, scalar relativistic corrections included, respective experimental excitation energy of $^{12}C$ has been reproduced with accuracy of about 7 cm$^{-1}$.

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Krzysztof Strasburger. 2019-03-14. Explicitly correlated wavefunctions of the ground state and the lowest quintuplet state of the carbon atom. https://doi.org/10.1103/physreva.99.069901

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