Ultrafast dynamics of photoexcited carriers in vapor-phase fullerene

Understanding of the hot electron relaxation dynamics through intraband transitions in fullerene materials is invaluable in organic photovoltaics applications. In this work, we investigate the hot carrier relaxation of photoexcited C₆₀ molecule by using a scheme of ab initio non-adiabatic molecular dynamics simulations based on density functional theory [1-2]. The methodology is underpinned by a combination of the fewest-switch surface hopping approach and Kohn−Sham single-particle description [1]. Results indicate the relaxation of the excited population to the band edges that occurs on the ultrafast time scale driven by the dynamical electron-phonon coupling. The population lifetimes of the intermediate states largely map out the unoccupied ground state spectrum which may motivate experimental interests.  

[1] A V. Akimov and O.V Prezhdo, J. Chem. Theory Comput. 9, 11 (2013).

[2] M. Madjet et al. J. Phys. Chem. Lett 8, 18 (2017)