PDAs films with an ester group in allylic position to the conjugated system presented two
emission bands. The higher energy emission band was assigned to carbonyl emission and the lower energy emission band to self-trapped
excitons (STE). Indeed, the inclusion of metal salts incremented the intensity relation between the higher and lower emission energy
bands. On the other hand, Raman spectroscopy measurements performed in PDAs films derived of pentyn-1-ol indicated that the metal
salts induced a slight statistical shift in the triple and double bond signals to higher energies.