Abstract

Proton transfer is a fundamental and important process in biological systems. To understand this process in complicated biological activities, one fruitful approach is the investigation of simpler molecular systems to gain insight into the proton transfer dynamics. Salicylideneaniline (SA), shown in Fig. 1, is one of the most attractive molecules and was investigated extensively so far [1]. The basic understanding of excited state proton transfer in SA is as follows: In the ground state, the enol form is more stable than the keto form, while in excited states, the proton-transferred keto form is preferred. Thus, the proton of the hydroxy group migrates on a fs-timeacsle upon photoexcitation. From there, cis-trans isomerization takes place by passing a conical intersection with the ground state and produces a photochromic product : the trans-keto form.

© 2011 IEEE