Density Functional Theory Investigation of Simple N-Heterocyclic Carbenes Adsorbed on the Pd/Cu(111) Single-Atom Alloy Surface DOI Creative Commons
Scott Simpson

ACS Omega, Journal Year: 2025, Volume and Issue: unknown

Published: April 28, 2025

Nonlocal density functional theory calculations were utilized to investigate the interactions of four different cyclic N-heterocyclic carbenes with a Pd/Cu(111) single-atom alloy surface. We find that molecules are chemisorbed surface due relatively large binding energies and significant charge transfer between adsorbates. highlight modulating NHC backbone changes unoccupied states on adsorbates participate in back-donation from adsorbate. This contrasts forward donation (adsorbate HOMO surface) is left unchanged through modifying backbone.

Language: Английский

Studies on the Effect of Positive and Negative Charges on the 77Se NMR Shifts of Selenones and Selenenyls of N-heterocyclic Carbenes of Imidazolium-4,5-dicarboxylates DOI Creative Commons

Lucas Pruschinski,

Sean Ray Kahnert,

Colin Herzberger

et al.

The Journal of Organic Chemistry, Journal Year: 2025, Volume and Issue: unknown

Published: Feb. 4, 2025

1,3-Imidazole-4,5-dicarboxylic acid derivatives were investigated with respect to the properties of underlying N-heterocyclic carbenes. Their selenium adducts prepared as diesters, monoesters, and dianionic dicarboxylates. Se-methylation yielded selenenyls (cationic selenoethers). 77Se NMR shifts are considered a measure electronic carbene. Since they very sensitive external (solvent, pH, temperature, reference reagent, method) internal parameters (substituent effects, steric nonclassical H-bonding, anisotropy), difficulties can arise in reliably interpreting these values. Our model compounds allow systematic investigation influence charges on since both structural changes measurement conditions have been minimized. Depending charge, cover range from 42.1 ppm (dianionic dicarboxylate) via 65.0 (monoanionic 92.5 (neutral diester) 153.8 selenoether) DMSO-d6. The signals also show considerable solvent pH dependence, which was selection solvents (MeOD, CDCl3, CD2Cl2, CD3COOD, CD3CN, acetone-d6, THF-d8, pyridine-d5, toluene-d8, DMSO-d6) values D2O. Linear relationships found between HOMO LUMO energies shifts, respectively.

Language: Английский

Citations

1
Density Functional Theory Investigation of Simple N-Heterocyclic Carbenes Adsorbed on the Pd/Cu(111) Single-Atom Alloy Surface DOI Creative Commons
Scott Simpson

ACS Omega, Journal Year: 2025, Volume and Issue: unknown

Published: April 28, 2025

Nonlocal density functional theory calculations were utilized to investigate the interactions of four different cyclic N-heterocyclic carbenes with a Pd/Cu(111) single-atom alloy surface. We find that molecules are chemisorbed surface due relatively large binding energies and significant charge transfer between adsorbates. highlight modulating NHC backbone changes unoccupied states on adsorbates participate in back-donation from adsorbate. This contrasts forward donation (adsorbate HOMO surface) is left unchanged through modifying backbone.

Language: Английский

Citations

0