We next measured the delayed emission spectrum as a function of temperature of the respective 10 and 5 wt% films of 4DMAC-TPPQ and 4PXZ-TPPQ in CBP (Figures and Table ). There is an apparent shifting of the delayed emission, attributed to phosphorescence, as a function of temperature. The T1 state of 4DMAC-TPPQ red-shifts from 2.15 eV at 300 K to 2.06 eV at 200 K to 1.94 eV at 77 K (Figure and Table ). Similarly, the T1 state of 4PXZ-TPPQ red-shifts from 2.10 eV at 300 K to 2.02 eV at 200 K and 1.92 eV at 77 K (Figure and Table ). The apparent blue-shift shift of triplet states from 77 to 300 K in both molecules could be due to the fact that at 300 K the delayed emission originates from the monomer while at 77 K the delayed emission comes from the aggregate. This is supported by the TDA-DFT calculations (vide-supra).