Betkhoshvili, SergiMoreira, Ibério de Pinho RibeiroPoater i Teixidor, JordiBofill i Villà, Josep M.2025-07-252025-07-252024-01-011948-7185https://hdl.handle.net/2445/222595In this work, we provide a general strategy to stabilize the ground state of polyradical(oid)s and make higher spin states thermally accessible. As a proof of concept, we propose to merge two planar fully π-conjugated diradical(oid)s to obtain a planar and cross-conjugated tetraradical(oid). Using multireference quantum chemistry methods, we show that the designed tetraradical(oid) is stabilized by aromaticity and delozalization in the π-system and has six thermally accessible spin states within 1.72 kcal/mol. Analysis of the electronic structure of these six states of the tetraradical(oid) shows that its frontier π-system consists of two weakly interacting subsystems: aromatic cycles and four unpaired electrons. Conjugation between unpaired electrons, which favors closed-shell structures, is mitigated by delocalization and the aromaticity of the bridging groups, leading to the synergistic cross-coupling between two diradical(oid) subunits to stabilize the tetraradical(oid) electronic structure.7 p.application/pdfengcc-by (c) Betkhoshvili, Sergi et al., 2024http://creativecommons.org/licenses/by/3.0/es/Estructura químicaCompostos aromàticsEstructura electrònicaChemical structureAromatic compoundsElectronic structureinfo:eu-repo/semantics/article7561272025-07-25info:eu-repo/semantics/openAccess