Dynamical disorder affected transient absorption spectra: the excess energy degradation model

We employ a time resolved pump probe approach to strongly excited molecular aggregates to study disordering processes. The theory, which takes into account the effect of dynamic disordering in one-dimensional molecular systems, explains the experimentally measured features of the difference absorption spectra for PIC Cl J-aggregates fairly well. Specifically, the `blueshiftedʹ spectral position and magnitude of the difference absorption spectra are shown as appeared due to `hotʹ processes of off-diagonal disordering of an excited aggregate after the annihilation event.