Ultrafast nonadiabatic relaxation of photoexcited phenyl-C<sub>61</sub> butyric acid methyl ester molecule

POSTER

Abstract

Highly efficient polymer-fullerene based OPV devices employ polymer functionalized fullerenes P-Cn, such as phenyl-C61 butyric acid methyl ester (PCBM), as electron acceptors [1]. In general, the success of functional fullerenes as acceptors, electron selective layers, and morphology stabilizers of bulk heterojunction polymer solar cells is now established [2]. This high degree of versatility in P-Cn functionality in OPV makes a fundamental understanding of its hot carrier relaxation dynamics an essential test case to probe the process. In this work, we use an approach of electron-phonon coupled nonadiabatic molecular dynamics (NAMD) [3] to simulate the relaxation of a photoexcited PCBM molecule. The methodology relies on a combination of the fewest-switches surface hopping approach and Kohn−Sham single-particle description in density functional theory (DFT) using Libra software [4]. Comparisons with the results from pristine C60 will be made at various stages to capture the effects of polymer functionalization on the dynamics.

[1] G.J. Hedley et al, Nat. Commun. 4, 2867 (2013).

[2] C.-Z. Li et al, J. Mater. Chem. 22, 4161, (2012).

[3] M.E. Madjet et al, Phys. Rev. Lett. 126, 183002, (2021).

[4] M. Shakiba et al, Software Impacts 14 100445 (2022).

*National Science Foundation Grant No. PHY-2110318.BARTIK High-Performance Cluster at Northwest Missouri State University (National Science Foundation Grant No. CNS-1624416). Services provided by the PATh Facility [1,2,3,4], which is supported by the National Science Foundation Award No. 1836650:[1] Pordes, R. et al, (2007). The open science grid. J. Phys. Conf. Ser., 78, 012057. https://doi.org/10.1088/1742-6596/78/1/012057.[2] Sfiligoi, I. et al, (2009). The pilot way to grid resources using glideinWMS. 2009 WRI World Congress on Computer Science and Information Engineering, 2, 428–432. https://doi.org/10.1109/CSIE.2009.950.[3] OSG. (2015). Open Science Data Federation. OSG. https://doi.org/10.21231/0KVZ-VE57[4] PATh Facility. (2022). https://doi.org/10.21231/k4r7-s230

Publication: 1) "Ultrafast transfer and transient entrapment of photoexcited Mg electron in Mg@C60"; M.E. Madjet, E. Ali, M. Carignano, O. Vendrell, and H.S. Chakraborty, Phys. Rev. Lett. 126, 183002 (2021).
2) "Ultrafast nonadiabatic electron dynamics in photoexcited C60: a comparative study among DFT exchange-correlation functionals"; E. Ali, M.E. Madjet, R. De, and H.S. Chakraborty, submitted to Phys. Rev. A https://arxiv.org/abs/2306.16386.
3) "Ultrafast nonadiabatic relaxation of C60 with decoherence: DFT versus extended tight-binding model"; M. Wholey, R. De, M.E. Madjet, and H.S. Chakraborty, (Planned paper)

Presenters

  • Ruma De

    • Northwest Missouri State University

Authors

  • Matthew Wholey

    • Northwest Missouri State University

  • Joan Jimenez

    • Northwest Missouri State University

  • Ruma De

    • Northwest Missouri State University

  • Himadri S Chakraborty

    • Northwest Missouri State University
    • Department of Natural Sciences, Northwest Missouri State University, USA

  • Mohamed E Madjet

    • Department of Natural Sciences, Northwest Missouri State University, USA
    • Northwest Missouri State University