Time-resolved PL measurements were performed on the same films to investigate the TADF properties of the materials at both 300 K (room temperature) and at 80 K (LT). Previously reported Mes3-DiKTa was used as the benchmark reference material, and diluted in 0.1 wt% zeonex films to allow us to study the HAEs without significant additional complexity due to intermolecular interactions. The time-resolved decays of the zeonex films are shown in Figure . With the introduction of bromine atoms, the prompt fluorescence (PF) and delayed fluorescence (DF) lifetimes become shorter, while the DF contribution to the overall emission increases (Table ).Thus, tBr-DiKTa shows the best TADF response followed by dBr-tBu-DiKTa and Mes3-DiKTa -a clear indicator that the peripheral HAE assists in augmenting SOC.