RUI: Double Photoionization to Probe Electron Correlation in Atomic and Molecular Systems with More than Two Electrons

原子和分子是构成我们日常生活的世界的最简单的物体。这些原子和分子由原子核组成，原子核由质子和中子组成，周围环绕着大量的电子。原子和分子之间的相互作用，特别是化学相互作用，涉及电子的运动。自量子力学发现以来，探索这种运动的动力学，导致相互作用，一直是研究的主要焦点，量子力学的定律使我们能够计算这种运动。当一个原子或分子由大量的电子组成时，计算只能是近似的，而且非常困难，同时对理解化学的各个方面很重要。这个项目将着重于计算这些交互的一个子集。该研究将在本科院校进行，为本科生提供真正的研究经验的可能性。该项目将研究具有两个以上电子的小原子和分子的相关电子动力学的结果，以便更好地理解具有许多电子的不同目标原子和分子的异同。电子相关是一种对所有物质的行为和结构有重大影响的基本现象。几十年来，为了开发更精确的方法来解释即使是最简单的原子和分子中电子运动的非近似动力学，研究一直集中在束缚态（原子的能级，分子的势曲线等）上，但是这种相关性的后果也极大地影响了当两个电子被光子从目标中射出时所产生的双连续体。这些相关的电子相互作用是物质在原子水平上的组织和结构的基础，并且继续对研究和更好地理解至关重要。更全面地了解具有两个以上电子的简单原子和分子中的电子相关性，将会影响许多其他研究领域，包括化学、原子和分子物理学、分子生物学和材料科学，仅举几例。该项目将研究这些基本电子相关性对具有两个以上电子的非平凡原子和分子的影响，以便更好地理解保留在原子或双原子分子上的电子的初始和最终状态如何影响两个光电电子留下其他电子的方式。从第一原理描述这些事件的理论计算将应用于具有许多电子的目标，这些电子在光电离事件之前，期间和之后继续与完全相关的电子相互作用。人们希望这个项目能够进一步阐明所有束缚在原子或分子上的电子是如何影响那些将进入连续体的电子的，以及对称性和电子结构的结果是如何影响出射电子的。时间依赖和时间独立的方法都将被探讨。这项工作与这些系统的运动学完整实验研究密切相关。

Some of the simplest objects making up the world as we experience it on a day-to-day basis are atoms and molecules. These atoms and molecules consist of nuclei made up of protons and neutrons surrounded by a sea of electrons. Interactions among atoms and molecules, especially chemical interactions, involve the motion of the electrons. Exploring the dynamics of this motion, leading to interactions, has been a major focus of research since the discovery of quantum mechanics, whose laws allow us to calculate this motion. When an atom or molecule consists of a large number of electrons, the calculations can only be approximate and are extremely difficult, while at the same time being important for understanding aspects of chemistry. This project will focus on calculating a subset of these interactions. The research will be carried out at an undergraduate institution, offering the possibility of a true research experience for undergraduate students.This project will examine the consequences of correlated electron dynamics of small atoms and molecules with more than two electrons in order to better understand the similarities and differences in different target atoms and molecules that result from having many electrons. Electron correlation is a fundamental phenomena with great impacts on the behavior and structure of all matter. Many decades of research towards developing more accurate ways of accounting for the non-approximated dynamics of electronic motion in even the simplest atoms and molecules have been focused on bound states (energy levels of atoms, potential curves of molecules, etc.) but the consequences of this correlation also greatly impact the resulting double continua when two electrons are ejected from a target by photons. These correlated electron interactions are fundamental to the organization and structure of matter at the atomic level and continue to be of vital importance to study and better understand. Broader consequences of pursuing more a complete understanding of electron correlation in simple atoms and molecules with more than two electrons would impact many other fields of study, including chemistry, atomic and molecular physics, molecular biology, and material science, to name a few. This project will investigate the impacts of these fundamental electronic correlations for non-trivial atoms and molecules with more than two electrons in order to better understand the ways that the initial and final states of the electrons that remain bound to the atom or diatomic molecule can affect the two photoejected electrons leaving the others behind. Theoretical calculations describing these events from first principles will be applied to targets with many electrons that continue to interact with the fully correlated electrons before, during and after the photoionization event. It is hoped that this project can further elucidate the broader consequences of how all of the electrons bound to an atom or molecule can affect those that will be moved into the continuum and how consequences of symmetry and electronic structure impacts outgoing electrons. Both time-dependent and time-independent approaches will be explored. The work is closely coupled to kinematically complete experimental investigations of these systems.