A Quantum Wavepacket Study of State-to-State Photodissociation Dynamics of HOBr/DOBr  

HOBr/DOBr态到态光解动力学的量子波包研究

作　　者：Liang Zhang Bin Jiang 张良;蒋彬(中国科学技术大学化学物理系,合肥微尺度物质科学国家研究中心,安徽省高等学校表面与界面化学与能源催化重点实验室,合肥230026)

机构地区：[1]Hefei National Laboratory for Physical Science at the Microscale,Department of Chemical Physics,Key Laboratory of Surface and Interface Chemistry and Energy Catalysis of Anhui Higher Education Institutes,University of Science and Technology of China,Hefei 230026,China

出　　处：《Chinese Journal of Chemical Physics》2020年第2期173-182,I0002,I0003,共12页化学物理学报（英文）

基　　金：supported by the National Key R&D Program of China (2017YFA0303500);Anhui Initiative in Quantum Information Technologies(AHY090200).

摘　　要：Photodissociation of HOBr is an important step in the reaction network of the depletion of ozone in stratosphere.Here,we report the first three-dimensional potential energy surfaces for the lowest three singlet states for HOBr,based on high level multi reference configuration interaction calculations.Quantum dynamics calculations are performed with a real wavepacket method,yielding not only absorption spectra but also internal state and angular distributions of the photodissociation fragments.Our results agree quantitatively with the measured total absorption cross sections of HOBr in the ultraviolet region and reproduce well the observed vibrationally cold and rotationally hot OH/OD fragments via photodissociation of HOBr/DOBr at 266 nm.In addition,we predict that the recoil anisotropy parameters for OH/OD are close to the limiting value of a parallel transition,suggesting a rapid dissociation process at 266 nm following an in-plane transition from the ground state(1^1A')to the 21A'state.This is consistent with the experimental conclusion derived from the measured rotational alignment.However,spin and electronic angular momenta need to be taken into account in the future to achieve a more quantitative agreement with experiment.Our work is expected to motivate further experimental investigations for this benchmark system.

关 键 词：Potential energy surface Photodissociation dynamics WAVEPACKET 

分 类 号：O643.1[理学—物理化学] O644.1[理学—化学]