RT Journal Article T1 Synthesis of zwitterionic open-shell bilayer spironanographenes A1 Lión Villar, Juan A1 Fernández García, Jesús Manuel A1 Medina Rivero, Samara A1 Perles, Josefina A1 Wu, Shaofei A1 Aranda, Daniel A1 Wu, Jishan A1 Seki, Shu A1 Casado, Juan A1 Martín León, Nazario AB 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. PB Springer Nature YR 2025 FD 2025-04-30 LK https://hdl.handle.net/20.500.14352/120334 UL https://hdl.handle.net/20.500.14352/120334 LA eng NO Lión-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/s41557-025-01810-2 NO N.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). NO Ministerio de Ciencia, Innovación y Universidades NO Tomatto ERC NO Comunidad de Madrid NO MEXT Grant-in-Aid for Scientific Research (Japan) NO JST-CREST NO Universidad de Málaga DS Docta Complutense RD 26 feb 2026