Dual-State Ambipolar Charge Transport in Antiaromatic [4]cyclodibenzopentalene Single-Molecule Nanohoops
Antiaromatic compounds are of great interest due to their narrow highest occupied molecular orbital (HOMO)-lowest unoccupied molecular orbital (LUMO) gaps, high reactivity, and enhanced charge mobility, yet their role in single-molecule electronics is still not well understood. Using electrochemically controlled scanning tunneling microscopy break junction (ECSTM-BJ) measurements, we compared the energy-alignment-dependent conductance of the aromatic [10]cycloparaphenylene ([10]CPP) and the antiaromatic [4]cyclodibenzopentalene ([4]CDBP). While [10]CPP showed a single conductance state via the HOMO, [4]CDBP exhibited two distinct states involving both the HOMO and LUMO. Our analysis and DFT calculations attribute this dual-state behavior to unique anchoring mode and energy-level realignment within a narrow HOMO-LUMO gap. This property enables electron- and hole-dominated pathways that depend on the anchoring configuration and coexist at a fixed gate potential. This phenomenon, also observed in the [4]CDBP⊃C<sub>60</sub> structure, highlights the potential of antiaromatic molecules for advanced molecular electronics.
Authors
- Andrej Weber (ORCID: https://orcid.org/0009-0006-0462-025X)
- Sai Feng
- Colin J. Lambert (ORCID: https://orcid.org/0000-0003-2332-9610)
- Yueqi Li (ORCID: https://orcid.org/0000-0001-7003-1978)
- Birgit Esser (ORCID: https://orcid.org/0000-0002-2430-1380)
- Qingqing Wu (ORCID: https://orcid.org/0000-0002-1520-4984)
- Renad Almughathawi
- Jan S. Wössner (ORCID: https://orcid.org/0000-0003-2170-4798)
- Jinghong Li (ORCID: https://orcid.org/0000-0002-0750-7352)
- Songjun Hou
- Chengyang Zhang (ORCID: https://orcid.org/0000-0001-6361-717X)
Institutions
- University of Science and Technology of China (CN)
- University of Freiburg (DE)
- Universität Ulm (DE)
- Taibah University (SA)
- Hefei National Center for Physical Sciences at Nanoscale (CN)
- Microscale (United States) (US)
- Institute of Bioorganic Chemistry (BY)
- Lancaster University (GB)
- Tsinghua University (CN)
Publication Details
- Journal
- Journal of the American Chemical Society
- Published
- 2025-05-19
- DOI
- https://doi.org/10.1021/jacs.4c17115
- Citations
- 4
- Primary Topic
- Molecular Junctions and Nanostructures
- Type
- article
- Field-Weighted Citation Impact
- 2.92
Funders
- Leverhulme Trust
- Deutsche Forschungsgemeinschaft
- National Natural Science Foundation of China
- Taibah University
- Ministry of Education – Kingdom of Saudi Arabi
- Engineering and Physical Sciences Research Council
- National Key Research and Development Program of China