In an effort to improve the spin coupling in single-molecule magnets, we rationally designed a new buildingblock molecule with significantly enhanced spin coupling compared to a previously established molecule. We relate this to a stabilization of aromaticity in the central connecting carbon ring, promoting the spin-polarization mechanism. This correlation between magnetic and electronic properties is supported by bulk measurements as well as submolecularly resolved scanning tunneling microscopy and spectroscopy experiments, where we found distinct differences in the local density of states distribution of the two molecules, especially at the central carbon ring. While the established molecule exhibits localized, spatially decoupled and even switchable states, the improved building block exhibits symmetric local density of states delocalized over the entire molecule, also revealing that this main characteristic electronic property is preserved upon adsorption on a metal surface. Due to their planar geometry, these molecules can serve as model systems for scanning-probe based studies of molecular magnetism.
We have used two different unconventional preparation techniques, namely, pulse injection and rapid heating, to deposit large trinuclear transition-metal complexes onto a Au(111) surface under ultrahigh-vacuum conditions. Both techniques turn out to provide a clean preparation and leave the molecules intact upon deposition. While pulse injection leads to isolated molecules on the surface, rapid heating yields close-packed ordered monolayer islands. From a comparison of topographies and electronic structures we conclude that both molecule−substrate and intermolecular interactions are relatively weak. We discuss the reasons for the appearance of the different structures and give a detailed comparison of both deposition techniques which allows us to evaluate their specific advantages and drawbacks. Our results show that these relatively simple and cost-efficient preparation techniques are suitable for nanoscale studies of large molecules such as single-molecule magnets.
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.