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arXiv · 1811.10522

Effects of core space and excitation levels on ground-state correlation and photoionization dynamics of Be and Ne

Juan J. Omiste·Lars Bojer Madsen
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Abstract

We explore the effects of correlation on the ground-state energies and on photoionization dynamics in atomic Be and Ne. We apply the time-dependent restricted-active-space self-consistent-field method for several excitation schemes and active orbital spaces with and without a dynamic core to address the effects systematically at different levels of approximation. For the ground-state many-electron wave functions, we compare the correlation energies with entropic measures of entanglement. A larger magnitude of the correlation energy does not always correspond to a larger value of the considered entanglement measures. To evaluate the impact of correlation in a process involving continua, we consider photoionization by attosecond pulses. The photoelecton spectra may be significantly affected by including a dynamical core.

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Juan J. Omiste, Lars Bojer Madsen. 2018-11-26. Effects of core space and excitation levels on ground-state correlation and photoionization dynamics of Be and Ne. https://doi.org/10.1063/1.5082940

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