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arXiv · 2404.18787

Understanding Radicals via Orbital Parities

Reza G. Shirazi·Benedikt M. Schoenauer·Peter Schmitteckert·Michael Marthaler·Vladimir Rybkin
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Abstract

We introduce analysis of orbital parities as a concept and a tool for understanding radicals. Based on fundamental reduced one- and two-electron density matrices, our approach allows us to evaluate a total measure of radical character and provides spin-like orbitals to visualize real excess spin or odd electron distribution of singlet polyradicals. Finding spin-like orbitals aumotically results in their localization in the case of disjoint (zwitterionic) radicals and so enables radical classification based on spin-site separability. We demonstrate capabilities of the parity analysis by applying it to a number of polyradicals and to prototypical covalent bond breaking.

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Reza G. Shirazi, Benedikt M. Schoenauer, Peter Schmitteckert, Michael Marthaler, Vladimir Rybkin. 2024-04-29. Understanding Radicals via Orbital Parities. https://arxiv.org/abs/2404.18787

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