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arXiv · 2106.10355

On the inclusion of cusp effects in expectation values with explicitly correlated Gaussians

Péter Jeszenszki·Robbie T. Ireland·Dávid Ferenc·Edit Mátyus
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Abstract

This paper elaborates the integral transformation technique of [K. Pachucki, W. Cencek, and J. Komasa, J. Chem. Phys. 122, 184101 (2005)] and uses it for the case of the non-relativistic kinetic and Coulomb potential energy operators, as well as for the relativistic mass-velocity and Darwin terms. The techniques are tested for the ground electronic state of the helium atom and new results are reported for the ground electronic state of the H$_3^+$ molecular ion near its equilibrium structure.

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Péter Jeszenszki, Robbie T. Ireland, Dávid Ferenc, Edit Mátyus. 2021-06-18. On the inclusion of cusp effects in expectation values with explicitly correlated Gaussians. https://arxiv.org/abs/2106.10355

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