Sample 1,3-PDA also shows a long-lived lifetime for its broad emission at 650 nm ( = 8.5 ns). Interestingly, in the high-resolution time-resolved measurement we also observe a narrowband component centered at 420 nm (FWHM = 20 nm), which has a very low intensity in the static PL measurements. This is related to its extremely short lifetime, which is shorter than the instruments response function indicating  < 3.5 ns: such rapid PL decay, coupled with the very low total intensity of this narrow band emission, points to emission from free exciton recombination that is swiftly quenched by transfer to states with red-shifted emission. Both the lifetime of narrow and broad emission of 1,3-PDA are almost an order of magnitude faster than the one of the sample 1,4-XDA: this is an indication, supported also by the brighter emission and higher activation energy for non-radiative pathways of the latter, that fast non-radiative recombination is the dominant mechanism in 1,3-PDA.