Fig. 2: Time-resolved photoluminescence (TRPL) measurements and comparison of measured and calculated SF rates.
From: Vacancy control in acene blends links exothermic singlet fission to coherence
a TRPL intensity of TET:6PH blends with different TET fractions in a 10-ns window. b Equivalent to a but in a 90-ns window. The arrows in a and b denote the direction of increasing TET fraction. c, d Comparison of experimentally (filled symbols) and theoretically (open circles) determined SF rate constants for TET- and PEN-based41 blends with varying concentrations of spacer molecules or the average number of nearest neighbours (NN). The experimental SF rates of TET:6PH and TET:PIC blends in c have been obtained by subtracting the monomeric decay rate (determined by fitting the 2% TET blend) from the decay rate of the prompt fluorescence, as explained in the text. The grey data points correspond to TET fractions where a phase separation of TET crystallites sets in (dark grey: TET:6PH, light grey: TET:PIC). The experimental data of PEN blends in d are adapted from Ref. 41. Error bars denote the 95% confidence interval of the fit.
