Mechanically tunable quantum interference in ferrocene-based single-molecule junctions Camarasa-Gómez, María Hernangómez-Pérez, Daniel Inkpen, Michael S. Lovat, Giacomo Fung, E-Dean Roy, Xavier Venkataraman, Latha ; https://orcid.org/0000-0002-6957-6089 Evers, Ferdinand Ferrocenes are ubiquitous organometallic building blocks that comprise a Fe atom sandwiched between two cyclopentadienyl (Cp) rings that rotate freely at room temperature. Of widespread interest in fundamental studies and real-world applications, they have also attracted some interest as functional elements of molecular-scale devices. Here we investigate the impact of the configurational degrees of freedom of a ferrocene derivative on its single-molecule junction conductance. Measurements indicate that the conductance of the ferrocene derivative, which is suppressed by 2 orders of magnitude as compared to a fully conjugated analogue, can be modulated by altering the junction configuration. Ab initio transport calculations show that the low conductance is a consequence of destructive quantum interference effects of the Fano type that arise from the hybridization of localized metal-based d-orbitals and the delocalized ligand-based π-system. By rotation of the Cp rings, the hybridization, and thus the quantum interference, can be mechanically controlled, resulting in a conductance modulation that is seen experimentally. American Chemical Society 2020 info:eu-repo/semantics/article doc-type:article text http://purl.org/coar/resource_type/c_6501 https://research-explorer.ista.ac.at/record/17908 Camarasa-Gómez M, Hernangómez-Pérez D, Inkpen MS, et al. Mechanically tunable quantum interference in ferrocene-based single-molecule junctions. <i>Nano Letters</i>. 2020;20(9):6381-6386. doi:<a href="https://doi.org/10.1021/acs.nanolett.0c01956">10.1021/acs.nanolett.0c01956</a> eng info:eu-repo/semantics/altIdentifier/doi/10.1021/acs.nanolett.0c01956 info:eu-repo/semantics/altIdentifier/issn/1530-6984 info:eu-repo/semantics/altIdentifier/e-issn/1530-6992 info:eu-repo/semantics/altIdentifier/pmid/32787164 info:eu-repo/semantics/openAccess