Atomic-Scale Observation of the Local Structure and 1D Quantum Effects in vdW Stacking Mo₆Te₆ Nanowires

The sub-nanometer-diameter transitional-metal chalcogenides (M₆X₆) molecular wires are ideal 1D quantum systems. The electronic properties of such system are very sensitive to the interface interaction and local imperfection. Here, the atomic structure and local electronic structure of van der Waals (vdW) stacking Mo₆Te₆ nanowires fabricated by using molecular beam epitaxy are reported. Atomic-resolution scanning tunneling microscopy measurement shows that the vdW interface distance varies from 0.71 to 1.05 nm when Mo₆Te₆ wires stacked on graphite, MoTe₂, and Mo₆Te₆ surfaces. Scanning tunneling spectroscopy confirmed the 1D quantum effect of van Hove singularity and Tomonaga–Luttinger liquid behavior at 77.8 K. Single Te vacancies and their effect to the local structure distortion are observed as well. These observations shed light on the local structure and quantum effects of the M₆X₆ nanowire materials, which may find applications in future electronic devices.