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Single photon triggered dianion formation in TCNQ and F4TCNQ crystals.

ABSTRACT: Excited state dynamics in two strong organic electron acceptor systems, TCNQ and F4TCNQ single crystals, was studied. After absorption of a single photon, dianions are formed in both crystals on ultrashort timescale: TCNQ τ < 50 fs, F4TCNQ τ = 4 ps. By use of transient absorption spectroscopy, we demonstrate that the dianion formation in F4TCNQ is mediated by the radical anion precursor which is described by a two-step model. Our measurements show the phenomenon that in this quinoid acceptor crystals in the absence of additional donor molecule, it is possible to resolve the two step formation of a doubly charged anion upon absorption of a single low energy photon (2.6 eV).

SUBMITTER: Ma L

PROVIDER: S-EPMC4921923 | biostudies-literature | 2016 Jun

REPOSITORIES: biostudies-literature

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Single photon triggered dianion formation in TCNQ and F4TCNQ crystals.

Ma Lin L Hu Peng P Jiang Hui H Kloc Christian C Sun Handong H Soci Cesare C Voityuk Alexander A AA Michel-Beyerle Maria E ME Gurzadyan Gagik G GG

Scientific reports 20160627

Excited state dynamics in two strong organic electron acceptor systems, TCNQ and F4TCNQ single crystals, was studied. After absorption of a single photon, dianions are formed in both crystals on ultrashort timescale: TCNQ τ < 50 fs, F4TCNQ τ = 4 ps. By use of transient absorption spectroscopy, we demonstrate that the dianion formation in F4TCNQ is mediated by the radical anion precursor which is described by a two-step model. Our measurements show the phenomenon that in this quinoid acceptor cry ...[more]

PMID: 27346797

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