Royal Society of ChemistryCruz, C. M.Márquez, I. R.Mariz, I. F. A.Blanco, V.Sánchez-Sánchez, C.Sobrado, J. M.Martín Gago, J. A.Cuerva, J. M.Maçôas, E.Campaña, A. G.2024-02-132024-02-132018-03-14Chemical Science 9: 3917(2018)2041-6520https://pubs.rsc.org/en/content/articlelanding/2018/sc/c8sc00427ghttp://hdl.handle.net/20.500.12666/937All publication charges for this article have been paid for by the Royal Society of Chemistry. Centro de Astrobiología INTA-CSIC, Torrejón de Ardoz, 28850 Madrid, Spain. Cruz, C. M. [0000-0002-0676-5210] ; Márquez, I. R. [0000-0001-9907-8040] ; Blanco, V. [0000-0002-6809-079X] ; Sánchez-Sánchez, C. [0000-0001-8644-3766] ; Martín-Gago, J. A. [0000-0003-2663-491X] ; Cuerva, J. M. [0000-0001-6896-9617] ; Maçôas, E. [0000-0001-8506-7025] ; Campaña, A. G. [0000-0001-5483-5642]Herein we describe a distorted ribbon-shaped nanographene exhibiting unprecedented combination of optical properties in graphene-related materials, namely upconversion based on two-photon absorption (TPA-UC) together with circularly polarized luminescence (CPL). The compound is a graphene molecule of ca. 2 nm length and 1 nm width with edge defects that promote the distortion of the otherwise planar lattice. The edge defects are an aromatic saddle-shaped ketone unit and a [5]carbohelicene moiety. This system is shown to combine two-photon absorption and circularly polarized luminescence and a remarkably long emission lifetime of 21.5 ns. The [5]helicene is responsible for the chiroptical activity while the push–pull geometry and the extended network of sp2 carbons are factors favoring the nonlinear absorption. Electronic structure theoretical calculations support the interpretation of the results.engAttribution-NonCommercial-NoDerivatives 4.0 Internationalhttps://creativecommons.org/licenses/by-nc-nd/4.0/info:eu-repo/semantics/articlehttps://doi.org/10.1039/C8SC00427G2041-6539info:eu-repo/semantics/openAccess