Dynamics of Hot Exciton Relaxation in Conjugated Polymer Chain

Yıl 2024, Cilt: 7 Sayı: 1, 1 - 8, 31.05.2024

Muhammet Erkan Köse , Esra Köse Zafer Erzurumluoğlu

https://doi.org/10.34088/kojose.1228645

Öz

Hot excitons are formed after photoexcitation of conjugated polymer chains. Hot excitons relax and convert into cold excitons with the aid of vibrational modes. In this study, the dynamics of such conversion is studied within the strong coupling regime. It has been found that the magnitudes of electronic coupling integrals for hot exciton relaxation are mostly due to exchange interactions between the interacting units. During relaxation, hot excitons oscillate back and forth between two different sites until they lose their extra energy. The time step for each oscillation has been found as small as 0.3 fs. It has also been found that photoexcited states in conjugated polymer chains do not necessarily localize at their initial location formed. Monte-Carlo simulations show that hot excitons can sustain their coherent motion along the conjugated backbone to some extent before total relaxation.

Anahtar Kelimeler

Conjugated Polymer, Dynamics, Energy Transfer, Exciton, Exchange Coupling

Destekleyen Kurum

The Scientific and Technical Research Council of Turkey

Proje Numarası

120Z662

Kaynakça

• [1] Scholes G.D., 2003. Long-range resonance energy transfer in molecular systems. Annual Review of Physical Chemistry, 54, pp. 57-87.
• [2] Collini E., Scholes G.D., 2009. Coherent Intrachain Energy Migration in a Conjugated Polymer at Room Temperature. Science, 323(5912), pp. 369-373.
• [3] Spano F.C., Clark J., Silva C., Friend R.H., 2009. Determining exciton coherence from the photoluminescence spectral line shape in poly(3-hexylthiophene) thin films. Journal of Chemical Physics, 130(7), no. 074904.
• [4] Kose M.E., Graf P., Kopidakis N., Shaheen S.E., Kim K., Rumbles G., 2009. Exciton Migration in Conjugated Dendrimers: A Joint Experimental and Theoretical Study. ChemPhysChem, 10(18), pp. 3285-3294.
• [5] Traub M.C., Lakhwani G., Bolinger J.C., Vanden Bout D., Barbara P.F., 2011. Electronic Energy Transfer in Highly Aligned MEH-PPV Single Chains. Journal of Physical Chemistry B, 115(33), pp. 9941-9947.
• [6] Hestand N.J., Spano F.C., 2018. Expanded Theory of H- and J-Molecular Aggregates: The Effects of Vibronic Coupling and Intermolecular Charge Transfer. Chemical Reviews, 118(15), pp. 7069-7163.
• [7] Duan H-G., Nalbach P., Prokhorenko V.I., Mukamel S., Thorwart M., 2015. On the origin of oscillations in two-dimensional spectra of excitonically-coupled molecular systems. New Journal of Physics, 17(7), no. 072002.
• [8] Kose M.E., Mitchell W.J., Kopidakis N., Chang C.H., Shaheen S.E., Kim K., Rumbles G., 2007. Theoretical Studies on Conjugated Phenyl-Cored Thiophene Dendrimers for Photovoltaic Applications. Journal of the American Chemical Society, 129(46), pp. 14257-14270.
• [9] Hwang I., Scholes G.D., 2011. Electronic Energy Transfer and Quantum-Coherence in pi-Conjugated Polymers. Chemistry of Materials, 23(3), pp. 610-620.
• [10] Maimaris M., Pettipher A.J., Azzouzi M., Walke D.J., Zheng X.J., Gorodetsky A., Dong Y.F., Tuladhar P.S., Crespo H., Nelson J., Tisch J.W.G., Bakulin A.A., 2022. Sub-10-fs observation of bound exciton formation in organic optoelectronic devices. Nature Communications, 13(1): no. 4949.
• [11] Garratt D., Misiekis L., Wood D., Larsen E.W., Matthews M., Alexander O., Ye P., Jarosch S., Ferchaud C., Struber C., Johnson A.S., Bakulin A.A., Penfold T.J., Marangos J.P., 2022. Direct observation of ultrafast exciton localization in an organic semiconductor with soft X-ray transient absorption spectroscopy. Nature Communications, 13(1), no. 3414.
• [12] Banerji N., Cowan S., Leclerc M., Vauthey E., Heeger A.J., 2010. Exciton Formation, Relaxation, and Decay in PCDTBT. Journal of the American Chemical Society, 132(49), pp. 17459-17470.
• [13] Rohr M.I.S., Marciniak H., Hoche J., Schreck M.H., Ceymann H., Mitric R., Lambert C., 2018. Exciton Dynamics from Strong to Weak Coupling Limit Illustrated on a Series of Squaraine Dimers. Journal of Physical Chemistry C, 122(15), pp. 8082-8093.
• [14] Zhang Y.S., Shi H.Y., Luo J.T., Shen J.G., Li S., George T.F., 2021. Lattice Vibrations and Time-Dependent Evolution of Local Phonon Modes during Exciton Formation in Conjugated Polymeric Molecules. Polymers, 13(11), no. 1724.
• [15] Perez I.G., Barford W., 2021. Ultrafast Fluorescence Depolarization in Conjugated Polymers. Journal of Physical Chemistry Letters, 12(22), pp. 5344-5348.
• [16] Hennebicq E., Pourtois G., Scholes G.D., Herz L.M., Russell D.M., Silva C., Setayesh S., Grimsdale A.C., Mullen K., Bredas J.L., Beljonne D., 2005. Exciton migration in rigid-rod conjugated polymers: An improved Forster model. Journal of the American Chemical Society, 127(13), pp. 4744-4762.
• [17] Bjorgaard J.A., Kose M.E., 2015. Simulations of singlet exciton diffusion in organic semiconductors: a review. Rsc Advances, 5(11), pp. 8432-8445.
• [18] You Z.Q., Hsu C.P., 2014. Theory and Calculation for the Electronic Coupling in Excitation Energy Transfer. International Journal of Quantum Chemistry, 114(2), pp. 102-115.
• [19] Harcourt R.D., Scholes G.D., Ghiggino K.P., 1994. Rate Expressions for Excitation Transfer. II. Electronic Considerations of Direct and through-Configuration Exciton Resonance Interactions. Journal of Chemical Physics, 101(12), pp. 10521-10525.
• [20] Cohen-Tannoudji C., Diu B., Laloe F., 1977. Quantum Mechanics, 1st ed., John Wiley and Sons, Paris, France.
• [21] Frisch M.J., Trucks G.W., Schlegel H.B., Scuseria G.E., Robb M.A., Cheeseman J.R., Scalmani G., Barone V., Mennucci B., Petersson G.A., Nakatsuji H., Caricato M., Li X., Hratchian H.P., Izmaylov A.F., Bloino J., Zheng G., Sonnenberg J.L., Hada M., Ehara M., Toyota K., Fukuda R., Hasegawa J., Ishida M., Nakajima T., Honda Y., Kitao O., Nakai H., Vreven T., Montgomery J.A., Peralta J.E., Ogliaro F., Bearpark M., Heyd J.J., Brothers E., Kudin K.N., Staroverov V.N., Kobayashi R., Normand J., Raghavachari K., Rendell A., Burant J.C., Iyengar S.S., Tomasi J., Cossi M., Rega N., Millam J.M., Klene M., Knox J.E., Cross J. B., Bakken V., Adamo C., Jaramillo J., Gomperts R., Stratmann R.E., Yazyev O., Austin A.J., Cammi R., Pomelli C., Ochterski J.W., Martin R.L., Morokuma K., Zakrzewski V.G., Voth G.A., Salvador P., Dannenberg J.J., Dapprich S., Daniels A.D., Farkas O., Foresman J.B., Ortiz J.V., Cioslowski J., Fox D.J., 2009. Gaussian 09, Revision B.01, Gaussian, Inc., Wallingford, CT.
• [22] Kose M.E., Long H., Kim K., Graf P., Ginley D., 2010. Charge Transport Simulations in Conjugated Dendrimers. Journal of Physical Chemistry A, 114(12), pp. 4388-4393.
• [23] Dimitrov S., Schroeder B., Nielsen C., Bronstein H., Fei Z., McCulloch I., Heeney M., Durrant J., 2016. Singlet Exciton Lifetimes in Conjugated Polymer Films for Organic Solar Cells. Polymers, 8(1), no. 14.
• [24] Kose M.E., 2011. An activated scheme for resonance energy transfer in conjugated materials. Journal of Chemical Physics, 135(24), no. 244512.
• [25] Wells N.P., Boudouris B.W., Hillmyer M.A., Blank D.A., 2007. Intramolecular exciton relaxation and migration dynamics in poly(3-hexylthiophene). Journal of Physical Chemistry C, 111(42), pp. 15404-15414.
• [26] Gierschner J., Cornil J., Egelhaaf H.J., 2007. Optical bandgaps of pi-conjugated organic materials at the polymer limit: Experiment and theory. Advanced Materials, 19(2), pp. 173-191.
• [27] Kose M.E., 2011. Evaluation of Excitonic Coupling and Charge Transport Integrals in P3HT Nanocrystal. Journal of Physical Chemistry C, 115(26), pp. 13076-13082.