Independence of the rate of the hot charge recombination in excited donor–acceptor complexes from the spectral density of high-frequency vibrations

Dynamic Solvent Effect on Ultrafast Charge Recombination Kinetics in Excited Donor–Acceptor Complexes

“…Within the framework of the stochastic point-transition approach, ,,,,,,,,− the CR kinetics of the excited DACs can be described by a set of differential equations for the probability distribution functions Here, ρ R ( Q 1 , Q 2 , t ) and ρ P ( n⃗ ) ( Q 1 , Q 2 , t ) are the probability distribution functions for the electronic excited state (reactant) formed by a short laser pulse in the charge transfer band and the neutral ground state (product) with the excitation of n α ( n α = 0, 1, 2, ...) vibrational quanta for αth intramolecular DAC modes with frequency Ω α (α = 0, 1, 2, ..., M ). Vector n⃗ has M components ( n 1 , n 2 , ..., n α , ..., n M ).…”

“…Electron transitions between the reactant state, U R , and the vibrational sublevels of the product state, U P ( n⃗ ) , are described by the parameters where F n⃗ is the Franck–Condon factor and S α = E rvα /ℏΩ α and E rvα are the Huang–Rhys factor and the reorganization energy of the αth high-frequency vibrational mode, respectively. Here, we use a universal spectral density of high-frequency vibrational modes for the DACs as previously the CR rate was shown to depend weakly on the vibrational spectral density provided the total reorganization energy, E rv = ∑ α E rvα , is constant and the number of high-frequency vibrational modes, M , is fixed. As the universal spectral density, we accept the high-frequency vibrational spectrum of the DAC consisting of phenylcyclopropane (PhCP) as the electron donor and tetracyanoethylene (TCNE) as the electron acceptor. , The values of the spectral parameters of complex PhCP–TCNE are given in Table .…”

“…Here, we use a universal spectral density of high-frequency vibrational modes for the DACs as previously the CR rate was shown to depend weakly on the vibrational spectral density provided the total reorganization energy, E rv = ∑ α E rvα , is constant and the number of high-frequency vibrational modes, M , is fixed. As the universal spectral density, we accept the high-frequency vibrational spectrum of the DAC consisting of phenylcyclopropane (PhCP) as the electron donor and tetracyanoethylene (TCNE) as the electron acceptor. , The values of the spectral parameters of complex PhCP–TCNE are given in Table .…”

“…As the universal spectral density, we accept the high-frequency vibrational spectrum of the DAC consisting of phenylcyclopropane (PhCP) as the electron donor and tetracyanoethylene (TCNE) as the electron acceptor. 56,64 The values of the spectral parameters of complex PhCP−TCNE are given in Table 1.…”

Influence of solvent viscosoty on thermal product yield of charge sepa-ration from second excited state in zinc-porphyrin derivatives

“…Время релаксации внутримолекулярной высокочастотной колебательной моды предполагается равным t v (1) = 0,05 пс [12]. и M = const скорость переноса а заряда слабо зависит от спектральной плотности [9]. Это означает, что в качестве хорошего приближения для любого донорно-акцепторного комплекса можно использовать универсальную спектральную плотность, включающую 5-10 высокочастотных колебательных мод.…”