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arXiv · 2310.11073

Second-order adiabatic connection: The theory and application to two electrons in a parabolic confinement

Andreas Savin·Jacek Karwowski
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Abstract

The adiabatic connection formalism, usually based on the first-order perturbation theory, has been generalized to an arbitrary order. The generalization stems from the observation that the formalism can be derived from a properly arranged Taylor expansion. The second-order theory is developed in detail and applied to the description of two electrons in a parabolic confinement (harmonium). A significant improvement relative to the first-order theory has been obtained.

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Andreas Savin, Jacek Karwowski. 2023-10-17. Second-order adiabatic connection: The theory and application to two electrons in a parabolic confinement. https://doi.org/10.1063/5.0167851

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