含硫小分子电子激发态势能面与态-态光解动力学的理论研究

光解动力学研究在模拟大气化学、燃烧化学和星际化学中的许多重要过程中都起着关键作用，也是理论与实验研究紧密结合并相互促进的典范。然而，许多重要小分子在真空紫外波段的态-态光解动力学研究并不完善，其微观机制仍不够明确。本项目拟从第一性原理出发并结合机器学习方法，构建H2S和SO2等含硫小分子体系的高精度电子激发态势能面及其非绝热耦合。在此基础上，利用量子波包动力学方法处理特定激发态的光解过程，获得相关分子及其同位素取代物的态-态光解动力学性质，为相关大气模型或星际化学模型提供可靠数据。通过理论与实验的紧密结合，逐步揭示分子的电子高激发态的光解特性，探索非绝热效应对光解动力学的影响，阐明光解过程中能量传递的本质。

Photodissociation dynamics plays a key role in simulating many important processes in atmospheric chemistry, combustion chemistry and interstellar chemistry, and is also a prototype for the close integration and mutual promotion of theoretical and experimental researches. However, the state-to-state photodissociation dynamics in vacuum ultraviolet band of many important small molecules have not been completed, and their micro-mechanisms have still not been fully understood. In this project, based on the first principles, the accurate potential energy surfaces and non-adiabatic couplings for the electronic excited states of H2S and SO2 molecular systems will be developed. Then, quantum wave packet method will be used to investigate the photodissociation dynamics of highly excited states for these systems and their isotopic substitutes to obtain the state-to-state dynamic information, which can provide reliable data for the related atmospheric models or interstellar chemical models. Through the close combination of theoretical and experimental studies, We will reveal the photodissociation characteristics of the highly excited states for those molecules, explore the influence of non-adiabatic effect on the photodissociation dynamics, and clarify the essence of energy transfer in those processes.