In degassed toluene, DMAC-TRZ and DMAC-py-TRZ have similar ΦPL of 67% and 58%, respectively, in line with emission originating in both compounds from a similar orthogonal geometry. The FPL decrease in air (ΦPL = 22% and 17%, respectively), indicating the presence of accessible triplet excited states. The prompt and delayed lifetimes, tp and td, for DMAC-TRZ in degassed toluene are of 20.8 ns (1.1%) and 5.2 µs (98.9%), in line with those previously reported, while the tp and td for DMAC-py-TRZ are 44.0 ns (8.1%) and 1.5 µs (91.9%), respectively (Figure ).