Excited-State Dynamics of a Benzotriazole Photostabilizer: 2-(2′-Hydroxy-5′-methylphenyl)benzotriazole

摘要: A large number of common photostabilizers are based on the 2-(2′-hydroxyphenyl)benzotriazole structure. One example is 2-(2′-hydroxy-5′-methylphenyl)benzotriazole, or TINUVIN-P. The excited-state dynamics this molecule have been extensively characterized by ultrafast spectroscopies. These experiments established that upon photoexcitation TINUVIN-P exhibits proton transfer followed a remarkably fast internal conversion. We simulate using ab initio multiple spawning (AIMS) and complete active space configuration interaction (CASCI) wave function with correction from density functional theory (DFT) to generate potential energy surfaces. predict order 20 fs simultaneous twisting pyramidalization until seam conical intersection reached. Near population ground state highly efficient. process best described as ballistic wavepacket motion...