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N-heterocyclic carbenes(NHCs) have garnered the attention of material scientists and chemists for their tunable electronic properties. NHCs anchored to surfaces have attractive features and may provide new applications that traditional self-assembled monolayers (SAMs) have yet to be employed. In-fact, NHCs have been utilized to functionalize surfaces to tune reactivity and/or selectivity. However, the underlying mechanisms to control the surface-adsorbate interaction is still in its infancy, especially for SAAs. Herein we utilize periodic non-local density functional theory (DFT) calculations to better understand how changing the NHC backbone influences the bonding between the surface and the adsorbate with the end goal to utilize a relatively new mechanism to store hydrogen.
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Density Functional Theory Investigation of Simple N-Heterocyclic Carbenes Adsorbed on the Pd/Cu(111) Single-Atom Alloy Surface
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 the molecules are chemisorbed to the surface due to relatively large binding energies and significant charge transfer between the surface and the adsorbates. We highlight that modulating the NHC backbone changes the unoccupied states on the adsorbates that participate in back-donation from the surface to the adsorbate. This contrasts with the forward donation (adsorbate HOMO to the surface) that is left relatively unchanged through modifying the backbone.
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- Award ID(s):
- 2142874
- PAR ID:
- 10632090
- Publisher / Repository:
- American Chemical Society
- Date Published:
- Journal Name:
- ACS Omega
- ISSN:
- 2470-1343
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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- Free Publicly Accessible Full Text
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Accepted Manuscript
- Journal Article:
- https://doi.org/10.1021/acsomega.4c11197
