{"das_tickbox":"1","OA_place":"publisher","PlanS_conform":"1","fulldoi":"https://doi.org/10.1021/acsnanoscienceau.6c00052","day":"19","OA_type":"gold","scopus_import":"1","date_published":"2026-08-19T00:00:00Z","file_date_updated":"2026-10-14T07:07:43Z","publication_status":"published","article_type":"original","month":"08","author":[{"full_name":"Bro-Jørgensen, William","first_name":"William","last_name":"Bro-Jørgensen"},{"last_name":"Lin","id":"a25c6e57-a657-11ef-8665-c4906b069ffc","first_name":"Junfeng","full_name":"Lin, Junfeng"},{"full_name":"Hamill, Joseph M.","first_name":"Joseph M.","last_name":"Hamill"},{"full_name":"Solomon, Gemma C.","last_name":"Solomon","first_name":"Gemma C."}],"date_created":"2026-10-12T12:01:45Z","type":"journal_article","tmp":{"name":"Creative Commons Attribution 4.0 International Public License (CC-BY 4.0)","image":"/images/cc_by.png","legal_code_url":"https://creativecommons.org/licenses/by/4.0/legalcode","short":"CC BY (4.0)"},"title":"Machine learning-enhanced molecular dynamics of 4,4′-bipyridinein a break junction: A supramolecular origin of the high conductance","DOAJ_listed":"1","publication":"ACS Nanoscience Au","citation":{"ieee":"W. Bro-Jørgensen, J. Lin, J. M. Hamill, and G. C. Solomon, “Machine learning-enhanced molecular dynamics of 4,4′-bipyridinein a break junction: A supramolecular origin of the high conductance,” <i>ACS Nanoscience Au</i>, vol. 6, no. 4. American Chemical Society, pp. 662–673, 2026.","mla":"Bro-Jørgensen, William, et al. “Machine Learning-Enhanced Molecular Dynamics of 4,4′-Bipyridinein a Break Junction: A Supramolecular Origin of the High Conductance.” <i>ACS Nanoscience Au</i>, vol. 6, no. 4, American Chemical Society, 2026, pp. 662–73, doi:<a href=\"https://doi.org/10.1021/acsnanoscienceau.6c00052\">10.1021/acsnanoscienceau.6c00052</a>.","apa":"Bro-Jørgensen, W., Lin, J., Hamill, J. M., &#38; Solomon, G. C. (2026). Machine learning-enhanced molecular dynamics of 4,4′-bipyridinein a break junction: A supramolecular origin of the high conductance. <i>ACS Nanoscience Au</i>. American Chemical Society. <a href=\"https://doi.org/10.1021/acsnanoscienceau.6c00052\">https://doi.org/10.1021/acsnanoscienceau.6c00052</a>","ama":"Bro-Jørgensen W, Lin J, Hamill JM, Solomon GC. Machine learning-enhanced molecular dynamics of 4,4′-bipyridinein a break junction: A supramolecular origin of the high conductance. <i>ACS Nanoscience Au</i>. 2026;6(4):662-673. doi:<a href=\"https://doi.org/10.1021/acsnanoscienceau.6c00052\">10.1021/acsnanoscienceau.6c00052</a>","ista":"Bro-Jørgensen W, Lin J, Hamill JM, Solomon GC. 2026. Machine learning-enhanced molecular dynamics of 4,4′-bipyridinein a break junction: A supramolecular origin of the high conductance. ACS Nanoscience Au. 6(4), 662–673.","short":"W. Bro-Jørgensen, J. Lin, J.M. Hamill, G.C. Solomon, ACS Nanoscience Au 6 (2026) 662–673.","chicago":"Bro-Jørgensen, William, Junfeng Lin, Joseph M. Hamill, and Gemma C. Solomon. “Machine Learning-Enhanced Molecular Dynamics of 4,4′-Bipyridinein a Break Junction: A Supramolecular Origin of the High Conductance.” <i>ACS Nanoscience Au</i>. American Chemical Society, 2026. <a href=\"https://doi.org/10.1021/acsnanoscienceau.6c00052\">https://doi.org/10.1021/acsnanoscienceau.6c00052</a>."},"publication_identifier":{"issn":["2694-2496"]},"doi":"10.1021/acsnanoscienceau.6c00052","issue":"4","quality_controlled":"1","pmid":1,"oa_version":"Published Version","language":[{"iso":"eng"}],"external_id":{"chemrxivid":["10.26434/chemrxiv-2025-wt6rd/v2"],"pmid":["42630769"]},"volume":6,"researchdata_availability":"yes","year":"2026","dataavailabilitystatement":"Input and output files for the MD trajectories are available in our ioChem-BD repository (85) and can be accessed here: 10.19061/iochem-bd-9-14. Raw data for all MD trajectories are available here: 10.17894/ucph.78aa9ec7-d132-447f-aaf0-8e6e5d59d8ea","abstract":[{"lang":"eng","text":"In single-molecule electronics, 4,4′-bipyridine is a well-characterized molecule that serves both as a fundamental testbed for developing experimental methodologies and showcases the complex behaviors expected from molecular electronic components. In break junction experiments, it is generally understood to exhibit a high- and a low-conductance state that are attributed to a tilted and stretched single-molecule configuration. Despite this established view, we suggest a supramolecular origin for these conductance states that has not previously been considered. Our findings indicate that the high- and low-conductance states may arise from the presence of two molecules and one molecule, respectively, challenging the conventional interpretation. Using a state-of-the-art machine learning force field called the neuroevolution potential, we find that the conventional interpretation of a tilted and stretched configuration is inconsistent with our simulations. Instead, our results suggest that the presence of two molecules promotes junction geometries and gold rearrangements that stabilize a high-conductance state whose transmission exceeds twice that of the low-conductance state. Furthermore, we compare this interpretation to the existing literature of diverse experimental data on 4,4′-bipyridine in break junctions and find that it is consistent with the broader body of experimental evidence. Our results highlight the structural complexity of molecular behavior within break junctions, suggesting even more complex dynamics than originally anticipated. In this light, a broader examination of the dynamics of molecules in single-molecule break junctions with machine learning-assisted molecular dynamics is warranted."}],"file":[{"date_updated":"2026-10-14T07:07:43Z","date_created":"2026-10-14T07:07:43Z","creator":"dernst","success":1,"file_size":6463446,"file_name":"2026_ACSNanoscienceAu_BroJorgensen.pdf","checksum":"87cc93f52ba508a7d19d7c03e9ef55cb","file_id":"23135","content_type":"application/pdf","relation":"main_file","access_level":"open_access"}],"_id":"23111","page":"662-673","date_updated":"2026-10-14T07:09:01Z","status":"public","article_processing_charge":"Yes","department":[{"_id":"LaVe"}],"intvolume":"         6","supplementarymaterial":"yes","has_accepted_license":"1","publisher":"American Chemical Society","chemrxivid":1,"user_id":"2DF688A6-F248-11E8-B48F-1D18A9856A87","acknowledgement":"The authors thank Latha Venkataraman for fruitful discussions about the main results of this paper. This project has received funding from the European Research Council (ERC) under the European Union’s Horizon 2020 research and innovation programme (grant agreement No. 865870). Junfeng Lin thanks the Institute of Science and Technology Austria for support.","oa":1,"ddc":["540"]}