計算科学コロキウム

第108回計算科学コロキウムを6月22日(水)15:00より行います。

第108回計算科学コロキウムを、6月22日(水)に開催します。
多数のご来聴をお願い致します。

日時:2016年6月22日(水)15:00-17:00
場所:筑波大学計算科学研究センター ワークショップ室
題目:Multi-state ab initio on-the-fly trajectory surface-hopping molecular dynamic simulation for azobenzene photoisomerization
講師:Prof. Chaoyuan ZhuDepartment of Applied Chemistry, National Chiao Tung University

要旨:
We developed a novel method to simulate analytical nonadiabatic switching probability estimated from electronically adiabatic potential energy surfaces and its gradients along on-the-fly trajectory. The present method can be immediately applied photochemical processes for localized nonadiabatic transitions induced by conical intersection. We could be able to perform on-the-fly trajectory surface hopping at the CASSCF quantum chemistry level to probe nπ* and ππ* azobenzene photoisomerization dynamics within four singlet low-lying electronic states (S0, S1, S2, and S3) coupled with complicated conical intersection network. From cis-to-trans, two-step fast-fast processes have the lifetime from several tenths to hundred femtoseconds, two-step fast-slow and slow-slow processes have lifetime from the several hundreds to thousand femtoseconds. From trans-to-cis, situation is more complicated and slow and fast motions are all mixed up. For trajectories started from S2 state, the all mechanisms dominated by the torsion of CNNC and NNCC moiety, while for trajectories started from S3 state, the mixed torsion of CNNC and inversion of NNC motions were confirmed by the present nonadiabatic molecular dynamics simulation. Quantum yields and lifetimes are all in good agreement with the recent transient absorption spectroscopy experiment.

世話人:重田 育照