σ‐Electrons Responsible for Cooperativity and Ring Equalization in Hydrogen‐Bonded Supramolecular Polymers
| Autor: | Diego Cesario, Francesca Nunzi, Célia Fonseca Guerra, Stephanie C. C. van der Lubbe, Pascal Vermeeren, Lucas de Azevedo Santos |
|---|---|
| Přispěvatelé: | Theoretical Chemistry, AIMMS |
| Rok vydání: | 2021 |
| Předmět: |
chemistry.chemical_classification
Quantitative Biology::Biomolecules Squaramide Cooperativity General Chemistry Ring (chemistry) Antibonding molecular orbital energy decomposition analysis supramolecular chemistry Supramolecular polymers Crystallography chemistry density functional calculations hydrogen bonds cooperative effects Single bond Molecular orbital Physics::Chemical Physics Lone pair |
| Zdroj: | ChemPlusChem, 87(2):e202100436. Wiley-VCH Verlag Santos, L A, Cesario, D, Vermeeren, P, Lubbe, S C C, Nunzi, F & Guerra, C F 2021, ' σ-Electrons Responsible for Cooperativity and Ring Equalization in Hydrogen-Bonded Supramolecular Polymers ', ChemPlusChem, vol. 87, no. 2, e202100436 . https://doi.org/10.1002/cplu.202100436 ChemPlusChem, 87(2). WILEY-V C H VERLAG GMBH |
| ISSN: | 2192-6506 |
| Popis: | We have quantum chemically analyzed the cooperative effects and structural deformations of hydrogen-bonded urea, deltamide, and squaramide linear chains using dispersion-corrected density functional theory at BLYP-D3(BJ)/TZ2P level of theory. Our purpose is twofold: (i) reveal the bonding mechanism of the studied systems that lead to their self-assembly in linear chains; and (ii) rationalize the C-C bond equalization in the ring moieties of deltamide and squaramide upon polymerization. Our energy decomposition and Kohn-Sham molecular orbital analyses reveal cooperativity in all studied systems, stemming from the charge separation within the sigma-electronic system by charge transfer from the carbonyl oxygen lone pair donor orbital of one monomer towards the sigma* N-H antibonding acceptor orbital of the neighboring monomer. This key orbital interaction causes the C=O bonds to elongate, which, in turn, results in the contraction of the adjacent C-C single bonds that, ultimately, makes the ring moieties of deltamide and squaramide to become more regular. Notably, the pi-electron delocalization plays a much smaller role in the total interaction between the monomers in the chain. |
| Databáze: | OpenAIRE |
| Externí odkaz: |
|
Plný text