A novel class of $Ï$/$Ï$-separating orbital localization functionals

Gerald Knizia; Elvira Sayfutyarova

quantum chemistry

A novel class of $I ¨ $ / $I ¨ $ -separating orbital localization functionals

arXiv:2607.26310

summary

The paper introduces a new class of orbital localization functionals that use nucleus‑electron observables to maintain a clear separation between σ‑ and π‑orbitals in molecular systems.

Abstract

Orbital localization methods have a long history in quantum chemistry, as they provide a convenient way to describe individual chemical bonds and local properties. However, only a handful of localization functionals are known up to date, and most localization methods do not separate $I ¨ $ - and $I ¨ $ -orbitals, which is important to describe chemical bonding patterns and reactivity. In this work, we present a new class of localization functionals, based on nucleus-electron physical observables, that preserve $I ¨ $ - and $I ¨ $ -orbitals separation in molecular systems. We also present a general mechanism behind $I ¨ / I ¨ $ -separating variational localization which can be used for constructing a broader class of $I ¨ / I ¨ $ -separating localization functionals from other local physical quantities.

12 pages, 7 figures

Topics & keywords

#orbital localization #sigma-pi separation #electronic structure theory #variational methods #chemical bondinglocalization functionalσ/π orbital separationnucleus-electron observablesvariational localizationbonding analysis

A novel class of I¨/I¨-separating orbital localization functionals

Abstract

Topics & keywords

A novel class of $I ¨ $ / $I ¨ $ -separating orbital localization functionals