Photo switching of Salicylidene methyl Furyl amine: A Theoretical Photo dynamics Study

Potential energy surfaces (PES) for the ground and excited state intramolecular proton transfer (ESIPT) processes in N-salicilydene methyl furylamine(SMFA)have been studied usingCC2 level of theory. Our calculations suggest thenon-viability of ground state intramolecular proton transfer. Excited states PES calculations support the existence of ESIPT process in SMFA.The calculated results show that the intramolecular hydrogen bond were formed in the S0 state, and upon excitation, the intramolecular hydrogen bonds between - OH group and nitrogen atom would be strengthened in the S1 state, which can facilitate the proton transfer process effectively. The calculations indicate two S1/S0 conical intersections (CIs) which provide radiation-less decay to the ground state. At the CIs, two barrier-free reaction coordinates direct the excited system to the ground state of enol-type minimum.The keto-type S1 state attained by barrier less proton transfer is found to be unstable via a torsional motion, which provides fast access to a S1−S0 conical intersections. From the conical intersection, a barrier less reaction path directs the system back to the enol-type minimum of the S0 potential energy surface, thus closing the photocycle.