The rich photochemistry and photophysics of rhenium(I) pyta tricarbonyl complexes, [Re(CO)3(Pyta)(L)] + (where Pyta = 3-(2-pyridyl)-1,2,4-triazole, L = various monodentate ligands), have garnered considerable interest due to their high quantum yield emissions in solution at ambient temperature and their potential role as a PhotoCORMs. The electronic states of these complexes are characterized by the 5d orbitals of the rhenium atom and the low-lying π and π* orbitals localized on pyta ligand. Consequently, charge-transfer (CT), ligand-centered (LC), and metal-centered (MC) states appear as low-lying electronic excited states in their photochemistry. A detailed understanding of their energetics and dynamics is crucial for designing novel PhotoCORMs. The 3 MLCT state is optically accessed via singlet metal-to-ligand charge transfer ( 1 MLCT) state. The 3 MLCT state is populated via intersystem crossing (ISC) between singlet and triplet states, a process that can occur in several hundred femtoseconds. In recent times, the MLCT states have been extensively studied because their emissions and singlet-oxygen generation activities but studies for COrelease remains limited. Figure1: Geometrical representation of [Re(CO)3(Pyta)(TPP)] + .