Reassessing Spin-Coupled (Full Generalized Valence Bond) Descriptions of Ozone Using Three-Center Bond Indices.

Kód výsledku v IS VaVaI

<a href="https://www.isvavai.cz/riv?ss=detail&h=RIV%2F67985858%3A_____%2F17%3A00480523" target="_blank" >RIV/67985858:_____/17:00480523 - isvavai.cz</a>

Výsledek na webu

<a href="http://dx.doi.org/10.1016/j.comptc.2016.12.010" target="_blank" >http://dx.doi.org/10.1016/j.comptc.2016.12.010</a>

DOI - Digital Object Identifier

<a href="http://dx.doi.org/10.1016/j.comptc.2016.12.010" target="_blank" >10.1016/j.comptc.2016.12.010</a>

Jazyk výsledku

angličtina

Název v původním jazyce

Reassessing Spin-Coupled (Full Generalized Valence Bond) Descriptions of Ozone Using Three-Center Bond Indices.

Popis výsledku v původním jazyce

Domain-averaged Fermi hole analysis is carried out for the ground state of O3 at its equilibrium geometry using a complete-active-space self-consistent field CASSCF(18,14) wavefunction, based on a slightly expanded full-valence active space. This initial analysis is augmented with an examination of the corresponding localized natural orbitals (LNOs) and of the numerical values obtained with a new improved definition of three-center bond indices for correlated singlet systems. Much the same pattern of LNOs is observed when using instead a subsequent internally-contracted multiconfiguration-reference configuration interaction construction, which also provides very similar values for the three-center bond indices. This gives us confidence to use such bond indices, alongside relative energies and the electric dipole moment, to assess the relative merits of various combinations of spin-coupled (full generalized valence bond) components with ten active electrons: four π, four σ bonding and the two nonbonding σ electrons associated with the central O atom. These multi-component valence bond descriptions were generated either with or without subsequent orbital reoptimization. The description of the π system which emerges from all of our analysis conforms to a standard model of three-center four-electron π bonding that incorporates a nontrivial degree of (partial) diradical character. Whereas certain combinations of ten-electron spin-coupled components can faithfully reproduce such a picture, none of the individual rival components appears to have sufficient flexibility on its own.

Název v anglickém jazyce

Reassessing Spin-Coupled (Full Generalized Valence Bond) Descriptions of Ozone Using Three-Center Bond Indices.

Popis výsledku anglicky

Domain-averaged Fermi hole analysis is carried out for the ground state of O3 at its equilibrium geometry using a complete-active-space self-consistent field CASSCF(18,14) wavefunction, based on a slightly expanded full-valence active space. This initial analysis is augmented with an examination of the corresponding localized natural orbitals (LNOs) and of the numerical values obtained with a new improved definition of three-center bond indices for correlated singlet systems. Much the same pattern of LNOs is observed when using instead a subsequent internally-contracted multiconfiguration-reference configuration interaction construction, which also provides very similar values for the three-center bond indices. This gives us confidence to use such bond indices, alongside relative energies and the electric dipole moment, to assess the relative merits of various combinations of spin-coupled (full generalized valence bond) components with ten active electrons: four π, four σ bonding and the two nonbonding σ electrons associated with the central O atom. These multi-component valence bond descriptions were generated either with or without subsequent orbital reoptimization. The description of the π system which emerges from all of our analysis conforms to a standard model of three-center four-electron π bonding that incorporates a nontrivial degree of (partial) diradical character. Whereas certain combinations of ten-electron spin-coupled components can faithfully reproduce such a picture, none of the individual rival components appears to have sufficient flexibility on its own.

Druh

J_imp - Článek v periodiku v databázi Web of Science

CEP obor

—

OECD FORD obor

10403 - Physical chemistry

Projekt

—

Návaznosti

I - Institucionalni podpora na dlouhodoby koncepcni rozvoj vyzkumne organizace

Rok uplatnění

2017

Kód důvěrnosti údajů

S - Úplné a pravdivé údaje o projektu nepodléhají ochraně podle zvláštních právních předpisů

Název periodika

Computational and Theoretical Chemistry

ISSN

2210-271X

e-ISSN

—

Svazek periodika

1116

Číslo periodika v rámci svazku

Sl

Stát vydavatele periodika

NL - Nizozemsko

Počet stran výsledku

10

Strana od-do

40-49

Kód UT WoS článku

000409152500004

EID výsledku v databázi Scopus

2-s2.0-85008173487