氩原子内壳层电子激发态的动力学参数研究

The research of the inner-shell excitations of atoms and molecules is of significance to understand the electron-correlation effect and the influence of nucleus on the motion of electrons. Up to now, most of the investigations of the inner-shell excitations focus on the peak shape and energy levels, while the studies of the wave-function distributions of the inner-shell excited states in the momentum space are relatively rare. In this project, we intend to take advantage of the nonresonant inelastic x-ray scattering technique to obtain the wave-function distribution information and the corresponding dynamic parameters of the inner-shell excited states of argon, which is a classical system with closed shell electrons. In addition, deviations are found between the dynamic parameters of the valence-shell excited states of argon obtained by the x-ray scattering method and high-energy electron scattering method. So a comparison between the dynamic parameters of these two methods for the inner-shell excited states of argon will be helpful to understand the mechanism in the scattering processes.

原子分子内壳层电子激发态的研究对于了解原子分子中的电子关联效应及原子核对电子运动的影响具有重要意义。目前为止，大部分对内壳层电子激发态的研究还局限在激发谱的峰形及能级结构方面，而对内壳层电子激发态波函数在动量空间分布信息的研究则较少。本申请将利用同步辐射非共振非弹性X射线散射技术，选择氩原子这一典型的闭壳层电子体系，从实验上获取其多个内壳层电子激发态波函数的动量空间分布信息以及相应的动力学参数。同时，鉴于最近利用X射线散射技术和高能电子散射技术获得的氩原子价壳层电子激发态的动力学参数之间存在差异，本项目将对比这两种实验技术得到的氩原子内壳层电子激发态的动力学参数，深入探索高能光子散射和高能电子散射过程背后的物理机制。

本项目利用非弹性X射线散射技术开展了N2分子内壳层和价壳层电子激发态的动力学参数实验研究，获得了内壳层电子激发过程1σu→1πg、1σg→1πg和价壳层电子激发过程1Σg→1Πg、1Σg→1Δu的动力学参数实验基准数据。在此基础上，对比分析了高能电子散射技术得到的动力学参数数据，评估了高能电子散射过程中高阶效应的强弱。结果表明，对于多电子的N2分子体系，并不存在一般性的判断高阶散射效应强弱的判据。高阶散射效应既与入射电子能量相关，也与具体的电子激发过程相关，需要针对更多更复杂的多电子体系开展高阶散射效应的研究。