Molecular aromaticity: a quantum phenomenon
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Miquel Solà
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Dariusz W. Szczepanik
Abstract
To celebrate the International Year of Quantum Science and Technology (IYQ), we discuss how the concept of aromaticity emerges from the postulates of quantum mechanics. Based on this discussion, we analyze the case of cyclo [18]carbon, a molecule that was characterized for the first time in 2019 in a scanning tunneling microscope. From the very beginning, this molecule was classified as an aromatic molecule. In the present work, we challenge this classification and provide arguments to classify this molecule as a non-aromatic species.
Award Identifier / Grant number: 2021SGR623
Award Identifier / Grant number: ICREA Academia prize 2024 to M.S.
Funding source: Infrastruktura PL-Grid
Award Identifier / Grant number: PLG/2024/017801
Funding source: Ministerio de Ciencia, Innovación y Universidades
Award Identifier / Grant number: PID2023-147424NB-I00
Funding source: Narodowe Centrum Nauki
Award Identifier / Grant number: 2021/42/E/ST4/00332
Acknowledgments
M.S. thanks the financial support from the Agencia Española de Investigación (MCIN/AEI/10.13039/501100011033) for project PID2023-147424NB-I00 and from the Generalitat de Catalunya for Project 2021SGR623 and ICREA Academia prize 2024 to M.S. D.W.S. acknowledges financial support from the National Science Centre, Poland (2021/42/E/ST4/00332) and Polish high-performance computing infrastructure PLGrid (HPC Center: ACK Cyfronet AGH) for providing computer facilities and support within computational grant no. PLG/2024/017801.
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Research ethics: Not applicable.
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Informed consent: Not applicable.
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Author contributions: All authors have accepted responsibility for the entire content of this manuscript and approved its submission.
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Use of Large Language Models, AI and Machine Learning Tools: None declared.
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Competing interests: The authors state no conflict of interest.
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Research funding: Agencia Española de Investigación (MCIN/AEI/10.13039/501100011033) project PID2023- 147424NB-I00 Generalitat de Catalunya Project 2021SGR623 and ICREA Academia prize 2024 to M.S. National Science Centre, Poland Project 2021/42/E/ST4/00332 Polish high-performance computing infrastructure PLGrid Project PLG/2024/017801.
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Data availability: The authors confirm that the data supporting the findings of this study are available within the article.
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