The transient absorption data was collected using a homemade software (LabView, National Instruments, Inc.). Data was corrected prior to analysis for group velocity dispersion (GVD) of the WLC using the two-photon absorption signal of neat methanol. Global and target analyses of the femtosecond transient absorption data was done using the Glotaran software were a two-component sequential model was used. Time zero was determined from the Raman stimulated emission from the solvent centered around 395 nm (when using PBS and ~390 nm when using acetonitrile, and exciting at 350 nm; ~355 nm using PBS and ~350 nm using acetonitrile, and exciting at 316 nm; ~375 nm using PBS and exciting at 334 nm). This band at its maximum amplitude was used to set time zero because it represents the maximum overlap of the pump and probe pulses. The uncertainties in the lifetimes are reported as twice the standard deviation (2) obtained from the global fit analysis using the Glotaran software. The percentage of the relative triplet yield for Aza were estimated by using equation (3):