It has been demonstrated that the single-molecule transport properties of fullerene C60 can be modulated by encapsulating endohedral species, i.e. Li+ and H2O, which exhibit different degrees of van der Waals interactions with the C60 cage.
Overcrowded ethylene 1 shows mechanochromic behavior with contrasting color change between yellow and violet arising from its conformational isomerization, which should also be accompanied by the change in the electronic structure. Here, we report a single-molecule electronic study of 1 using scanning tunneling microcopy (STM) and STM-based break junction techniques. The single-molecule junction of 1 sandwiched by Au electrodes showed two distinct high- and low-conductance states with the conductance values of 0.003 and 0.0002 G0. The high-conductance state is one order of magnitude more conductive than the low-conductance state. The two states can be ascribed to two conformational isomers of 1 in the junction.
In this paper, the tuning of the thermopower with single‐molecule junctions of fullerene (C60), 4,4′‐bipyridine (BPY), and p‐phenylenediamine (PPD) using scanning tunneling microscopy (STM)‐based break junction technique is demonstrated. Single‐molecule junctions are prepared in a nanogap between a Au‐STM tip and a Au(111) electrode. Upon applying a temperature difference across the junction, a thermoelectric voltage is generated across it. By mechanically controlling the tip–electrode separation distance, the thermoelectric voltage of the junction is tuned. The absolute value of the thermopower decreases with decreasing tip–electrode separation distance for BPY and PPD, while it increases for C60. Atomistic simulations of the junction illustrate how this arises from shifts in the conduction orbital energies induced by the mechanical compression of the junctions.
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.