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arXiv · 1702.06225

Minimally-corrected partial atomic charges for non-covalent electrostatic interactions

Rebecca Efrat Hadad·Roi Baer
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Abstract

We develop a new scheme for determining molecular partial atomic charges (PACs) with external electrostatic potential (ESP) closely mimicking that of the molecule. The PACs are the "minimal corrections" to a reference-set of PACs necessary for reproducing exactly the tensor components of the Cartesian zero- first- and second- molecular electrostatic multipoles. We evaluate the quality of ESP reproduction when "minimally correcting" (MC) Mulliken, Hirshfeld or iterated-Hirshfeld reference PACs. In all these cases the MC-PACs significantly improve the ESP while preserving the reference PACs' invariance under the molecular symmetry operations. When iterative-Hirshfeld PACs are used as reference the MC-PACs yield ESPs of comparable quality to those of the ChElPG charge fitting method.

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Rebecca Efrat Hadad, Roi Baer. 2017-02-21. Minimally-corrected partial atomic charges for non-covalent electrostatic interactions. https://arxiv.org/abs/1702.06225

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