[原分所] IAMS Lecture Announcement on December 19, 11:00 AM (Dr. Kaito Takahashi)
消息來源：原分所
截止日期：2013-12-13
Title: Coupling of electronic states and their imprint on reaction
Speaker: Dr. Kaito Takahashi (IAMS, Academia Sinica)
高橋開人博士 (本所助研究員)
Time: 11:00AM, December 19 (Thursday)
Place: Dr. Poe Lecture Hall, IAMS (本所浦大邦講堂 臺大校園內)
Contact: Dr. Kuei-Hsien Chen 陳貴賢博士
Abstract:
The back bone of present day quantum chemistry calculation lies on the Born-Oppenheimer approximation, where we separate nuclear and electronic motion, and calculate the electronic energy at a fixed nuclear geometry. Using this electronic energy, i.e. the adiabatic potential energy surface, we perform calculations to obtain optimized geometries, vibrational frequencies and reaction rates. In this talk I will focus on the theoretical studies for two systems where the strong coupling between electronic states causes this adiabatic picture to break down and greatly alter the gas phase reactions. In the first ClOOCl system, which is of interest in atmospheric studies, I will discuss the effect of avoided crossings and nonadiabatic coupling toward the photodissociation dynamics. In the second linear carbon chain cation Cn+ system, I will present calculation results which show that pseudo Jahn-Teller effects causes the ground electronic state of Cn+ (n=odd) to take a 2S state rather than the previously assumed 2P state. Furthermore, using a combination of theoretical calculation and isomer selected mass spectrometry experiments, I interrogate how this difference in electronic state is imprinted in the reaction products and rate of Cn++D2 (n=4-9) reaction.
Speaker: Dr. Kaito Takahashi (IAMS, Academia Sinica)
高橋開人博士 (本所助研究員)
Time: 11:00AM, December 19 (Thursday)
Place: Dr. Poe Lecture Hall, IAMS (本所浦大邦講堂 臺大校園內)
Contact: Dr. Kuei-Hsien Chen 陳貴賢博士
Abstract:
The back bone of present day quantum chemistry calculation lies on the Born-Oppenheimer approximation, where we separate nuclear and electronic motion, and calculate the electronic energy at a fixed nuclear geometry. Using this electronic energy, i.e. the adiabatic potential energy surface, we perform calculations to obtain optimized geometries, vibrational frequencies and reaction rates. In this talk I will focus on the theoretical studies for two systems where the strong coupling between electronic states causes this adiabatic picture to break down and greatly alter the gas phase reactions. In the first ClOOCl system, which is of interest in atmospheric studies, I will discuss the effect of avoided crossings and nonadiabatic coupling toward the photodissociation dynamics. In the second linear carbon chain cation Cn+ system, I will present calculation results which show that pseudo Jahn-Teller effects causes the ground electronic state of Cn+ (n=odd) to take a 2S state rather than the previously assumed 2P state. Furthermore, using a combination of theoretical calculation and isomer selected mass spectrometry experiments, I interrogate how this difference in electronic state is imprinted in the reaction products and rate of Cn++D2 (n=4-9) reaction.