Lión Villar, JuanFernández García, Jesús ManuelMedina Rivero, SamaraPerles, JosefinaWu, ShaofeiAranda, DanielWu, JishanSeki, ShuCasado, JuanMartín León, Nazario2025-05-212025-05-212025-04-30Lión-Villar, J., Fernández-García, J.M., Medina Rivero, S. et al. Synthesis of zwitterionic open-shell bilayer spironanographenes. Nat. Chem. (2025). https://doi.org/10.1038/s41557-025-01810-210.1038/s41557-025-01810-2https://hdl.handle.net/20.500.14352/120334N.M. and J.L.-V. thank the financial support from the Spanish MICINN (project number PID2020-114653RB-I00). N.M. and J.M.F.-G. thank the financial support by the ERC (SyG TOMATTO ERC-2020-951224). We also thank the support from the ‘(MAD2D-CM)-UCM’ project funded by Comunidad de Madrid, by the Recovery, Transformation and Resilience Plan, and by NextGenerationEU from the European Union. D.A. acknowledges the European Union—NextGenerationEU—Maria Zambrano fellowship. J.C. acknowledges MICINN (project number PID2021-127127NB-I00) and Junta de Andalucía (project numbers PROYEXCEL-0328 and FQM-0395) for financial support. Research Central Services (SCAI) of the University of Málaga, Unidad de Espectroscopía Vibracional (C. Capel and J. L. Zafra) are also acknowledged. On the Kyoto University side, S.S. was supported by MEXT Grant-in-Aid for Scientific Research (grant numbers 20H05862, 20H05867 and 22H00314) and JST-CREST (grant number JPMJCR23O3).Molecular nanographenes (NGs) are nanoscale graphene fragments obtained by organic synthetic protocols. Here we report the bottom-up synthesis of two spiro-NGs formed by two substituted hexa-peri-hexabenzocoronenes (HBCs), spiro-NG and F-spiro-NG. The X-ray crystal structure of the deca-tert-butyl-functionalized spiro-NG shows a bilayer disposition of the HBCs in face-to-face contact. By contrast, F-spiro-NG, which features tert-butyl substituents on one HBC unit, and fluorine on the other HBC unit, is an electron donor–acceptor bilayer NG. The structural assembly of the donor and acceptor graphenic layers enables an electron-transfer process that leads to the formation of a zwitterionic open shell, paramagnetic species constituted by a radical cation and a radical anion located in the donor and the acceptor HBCs, respectively. Magnetic and spectroelectrochemical experiments, together with theoretical calculations, support the persistent/dominant charge-separated nature of F-spiro-NG. Furthermore, photoconductivity measurements show a significant increase of the charge carrier mobility in the case of F-spiro-NG (Σμ = 6 cm2 V−1 s−1) compared with spiro-NG.engAttribution-NonCommercial-NoDerivatives 4.0 Internationalhttp://creativecommons.org/licenses/by-nc-nd/4.0/journal articlehttps://doi.org/10.1038/s41557-025-01810-2https://www.nature.com/articles/s41557-025-01810-2https://static-content.springer.com/esm/art%3A10.1038%2Fs41557-025-01810-2/MediaObjects/41557_2025_1810_MOESM1_ESM.pdfopen access54L65Molecular nanographenesOpen ShellSpironanographenesQuímica23 Química