Some implications of the Hartree product treatment of the quantum nuclei in the ab initio Nuclear-electronic orbital methodology

Masumeh Gharabaghi; Shant Shahbazian

doi:10.1016/j.physleta.2016.10.007

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arXiv · 1608.06860

Some implications of the Hartree product treatment of the quantum nuclei in the ab initio Nuclear-electronic orbital methodology

Masumeh Gharabaghi·Shant Shahbazian

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Abstract

In this letter the conceptual and computational implications of the Hartree product type nuclear wavefunction introduced recently within the context of the ab initio non-Born-Oppenheimer Nuclear-electronic orbital (NEO) methodology are considered. It is demonstrated that this wavefunction may imply a pseudo-adiabatic separation of the nuclei and electrons and each nucleus is conceived as a quantum oscillator while a non-Coulombic effective Hamiltonian is deduced for electrons. Using the variational principle this Hamiltonian is employed to derive a modified set of single-component Hartree-Fock equations which are equivalent to the multi-component version derived previously within the context of the NEO and, easy to be implemented computationally.

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Masumeh Gharabaghi, Shant Shahbazian. 2016-10-04. Some implications of the Hartree product treatment of the quantum nuclei in the ab initio Nuclear-electronic orbital methodology. https://doi.org/10.1016/j.physleta.2016.10.007

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