%0 Journal Article
%A Cruz, Carlos M
%A Márquez, Irene R
%A Mariz, Inês F A
%A Blanco, Victor
%A Sánchez-Sánchez, Carlos
%A Sobrado, Jesús M
%A Martín-Gago, José A
%A Cuerva, Juan M
%A Maçôas, Ermelinda
%A Campaña, Araceli G
%T Enantiopure distorted ribbon-shaped nanographene combining two-photon absorption-based upconversion and circularly polarized luminescence.
%D 2018
%@ 2041-6520
%U https://hdl.handle.net/10668/25623
%X 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.
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