Apparent vibrational side bands in rr-conjugated systems: the case of distyrylbenzene
The photoluminescence sPLd spectra of dilute solution and single crystals of distyrylbenzene show unique temperature-dependent vibronic structures. The characteristic single frequency progression at high temperatures is modulated by a low-frequency progression series at low temperatures. None of the series side-band modes corresponds to any of the distyrylbenzene Raman frequencies. We explain these PL properties using a time-dependent model with temperature-dependent damping, in which the many-mode system is effectively transformed to two “apparent” modes and then to a single apparent mode as damping increases.
Wu, C. C., Ehrenfreund, E., Gutierrez, J. J., Ferraris J. P., & Vardeny, Z. V. (2005). Apparent vibrational side bands in ∏-conjugated systems: the case of distyrylbenzene. Physical Review B, 71(8), 081201-1-4.