Torsional instability in the single-chain limit of a transition metal trichalcogenide

Journal Article · 20 July 2018 · Science

DOI: https://doi.org/10.1126/science.aat4749 · OSTI ID:1460921

Pham, Thang ^[1]; Oh, Sehoon ^[1]; Stetz, Patrick  ^[1]; Onishi, Seita ^[1]; Kisielowski, Christian ^[2]; Cohen, Marvin L. ^[1]; Zettl, Alex  ^[1]

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1. Univ. of California, Berkeley, CA (United States); Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States)
2. Molecular Foundry and Joint Center for Artificial Photosynthesis, Berkeley, CA (United States)

The scientific bounty resulting from the successful isolation of few to single layers of two-dimensional materials suggests that related new physics resides in the few- to single-chain limit of one-dimensional materials. Here,we report the synthesis of the quasi–one-dimensional transition metal trichalcogenide NbSe₃(niobium triselenide) in the few-chain limit, including the realization of isolated single chains. The chains are encapsulated in protective boron nitride or carbon nanotube sheaths to prevent oxidation and to facilitate characterization. Transmission electron microscopy reveals static and dynamic structural torsional waves not found in bulk NbSe₃crystals. Electronic structure calculations indicate that charge transfer drives the torsional wave instability. Finally, very little covalent bonding is found between the chains and the nanotube sheath, leading to relatively unhindered longitudinal and torsional dynamics for the encapsulated chains.

• Research Organization: Lawrence Berkeley National Laboratory (LBNL), Berkeley, CA (United States)
• Sponsoring Organization: USDOE Office of Science (SC), Basic Energy Sciences (BES) (SC-22). Materials Sciences & Engineering Division
• Grant/Contract Number: AC02-05CH11231
• OSTI ID: 1460921
• Alternate ID(s): OSTI ID: 1530369
• Journal Information: Science, Vol. 361, Issue 6399; ISSN 0036-8075
• Publisher: AAASCopyright Statement
• Country of Publication: United States
• Language: English