Molecular components are vital to introduce and manipulate quantum interference (QI) in charge transport through molecular electronic devices. Up to now, the functional molecular units that show QI are mostly found in conventional π‐ and σ‐bond‐based systems; it is thus intriguing to study QI in multicenter bonding systems without both π‐ and σ‐conjugations. Now the presence of QI in multicenter‐bond‐based systems is demonstrated for the first time, through the single‐molecule conductance investigation of carborane junctions. We find that all the three connectivities in carborane frameworks show different levels of destructive QI, which leads to highly suppressed single‐molecule conductance in para‐ and meta‐connected carboranes. The investigation of QI into carboranes provides a promising platform to fabricate molecular electronic devices based on multicenter bonds.

The identification of conformational isomers of the flexible molecule is challenging, owing to the rapid interconversion of isomers. By attaching two electrodes on a flexible molecule, cyclohexane, we accomplish the distinguishment of the two chair isomers of cyclohexane at room temperature using a single-molecule approach. The confinement effect of the attached electrodes not only plays an important role in identifying the chair isomers but also stabilizes the twist-boat intermediate that is showing a negligible distribution in the solution of cyclohexane.

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