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09:56
High Resolution Physical Characterization of Single Metallic Nanoparticles
Published on: June 28, 2019
Electron localization function and electron localizability indicator applied to study the bonding in the
Slawomir Berski1, Zdzislaw Latajka, Agnieszka J Gordon
1Faculty of Chemistry, University of Wroclaw, Wroclaw 54-210, Poland. sberski@wchuwr.pl
Journal of Computational Chemistry
|February 2, 2011
Summary
This study analyzes the electronic structure of peroxynitrous acid (HOONO) and its biradicaloid form. It reveals charge-shift bonds and identifies the O-O bond as the weakest, influencing HOONO dissociation.
Area of Science:
- Quantum Chemistry
- Theoretical Chemistry
- Chemical Physics
Background:
- Peroxynitrous acid (HOONO) is an important molecule in atmospheric and biological chemistry.
- Understanding its electronic structure is crucial for predicting its reactivity and stability.
- Previous studies have explored various isomers and properties of HOONO.
Purpose of the Study:
- To investigate the ground-state electronic structure of peroxynitrous acid (HOONO) and its singlet biradicaloid form (HO···ONO).
- To analyze the nature of the O-O and N-O bonds using topological methods.
- To determine the most favorable dissociation pathway for HOONO.
Main Methods:
- Utilized topological analysis of the electron localization function (ELF) and electron localizability indicator (ELI-D).
- Employed density functional theory (DFT) with B3LYP, M05, M052X, M06 functionals, alongside CCSD and CASSCF levels.
- Calculations were performed for three HOONO isomers (cis-cis, cis-perp, trans-perp) and biradicaloid forms.
Main Results:
- Identified charge-shift character for the N-O and O-O bonds, with the O-O bond being more electron-deficient.
- The B3LYP functional accurately predicted the geometrical structure of HOONO isomers.
- The most favorable dissociation pathway involves breaking the electron-deficient O-O bond (HOONO → HO + ONO).
Conclusions:
- HOONO exhibits unique bonding characteristics, including protocovalent and electron-depleted bonds.
- The O-O bond is the primary site for dissociation, leading to HO and ONO radicals.
- The electronic structure of the biradicaloid form (HO···ONO) shows a closed-shell O···O interaction with delocalized spins.
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