Tuning the binding mode of N-heterocyclic carbenes on metal surfaces is crucial for the development of new functional materials. To understand the impact of alkyl side groups on the formation of NHC species at the Au(111) surface, we combined scanning tunneling microscopy, X-ray photoelectron spectroscopy, and density functional theory calculations. We reveal two significantly different binding modes depending on the alkyl chain length. In the case of a short alkyl substituent, an up-standing configuration with one Au adatom is preferred, whereas the longer alkyl groups result exclusively in NHC-Au-NHC complexes lying flat on the surface. Our study highlights how well-defined structural modifications of NHCs allow for controlling the local binding motif on surfaces, which is important to design designated catalytic sites at interfaces.
The structural properties and binding motif of a strongly σ‐electron‐donating N‐heterocyclic carbene have been investigated on different transition‐metal surfaces. The examined cyclic (alkyl)(amino)carbene (CAAC) was found to be mobile on surfaces, and molecular islands with short‐range order could be found at high coverage. A combination of scanning tunneling microscopy (STM), X‐ray photoelectron spectroscopy (XPS), and density functional theory (DFT) calculations highlights how CAACs bind to the surface, which is of tremendous importance to gain an understanding of heterogeneous catalysts bearing CAACs as ligands.
Photoresponsive functional materials have gained increasing attention due to their externally tunable properties. Molecular switches embedded in these materials enable the controlo fp henomena at the atomicl evel by light. Metal-organic frameworks (MOFs) provide av ersatile platform to immobilize these photoresponsive units within defined molecular environments to optimize the intended functionality.F or the application of these photoresponsive MOFs (pho-MOFs), it is crucial to understand the influence of the switching state on the host-guest interaction. Therefore, we present ad etailed insight into the impact of molecular switching on the intermolecular interactions.B yp erforming atomistic simulations, we revealed that due to different interactions of the guest molecules with the two isomeric states of an azobenzene-functionalized MOF,b oth the adsorption sites and the orientation of the molecules within the pores are modulated. By shedding light on the host-guest interaction, our study highlights the unique potential of pho-MOFs to tailor molecular interaction by light.Supporting information and the ORCID identification number(s) for the author(s) of this article can be found under: https://doi.org/10.
Thiolate coordination networks (TCNs) were synthesized on metal surfaces using benzenehexathiol (BHT) and analyzed by cryogenic scanning tunneling microscopy (STM), X-ray photoelectron spectroscopy (XPS) as well as density functional theory. Upon adsorption, the deprotonation of the thiol groups occurred on the metal surface with the formation of metal-sulfur coordination bonds. Increasing the surface temperature triggered the complete dehydrogenation of BHT and promoted the formation of TCNs. On Ag(111), the TCN of [Ag 3 (C 6 S 6)] n was achieved and showed good thermal stability. On Cu(111), two TCNs ([Cu 6 (C 6 S 6)] n and [Cu 8 (C 6 S 6)] n ,) were identified. Interestingly, the construction of the two TCNs on Cu(111) can be precisely controlled by adjusting the temperature of the surface during deposition and thermal annealing. Our results reveal the significant influence of the metal surface on the formation of coordination networks.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.
hi@scite.ai
10624 S. Eastern Ave., Ste. A-614
Henderson, NV 89052, USA
Copyright © 2024 scite LLC. All rights reserved.
Made with 💙 for researchers
Part of the Research Solutions Family.