Temperature effect on the internal conversion dynamics following different stimulated absorptions in a conjugated polymer

After considering temperature effect, the internal conversion relaxation will take place transiently following different stimulated absorptions in a polymer (a), in which the transited electrons to the molecular orbital ε2∗ or ε3∗ will transit down to the lowest-energy orbital ε1∗ within an ultrafast time τ = 20 fs (b). It means that charge separation from the higher-lying excited states should be severely suppressed by their IC relaxations in the actual operation of a polymer solar cell.197