RUI: Double Photoionization to Probe Electron Correlation Many-Electron Molecules

电子相关是一种对所有物质的行为和结构产生重大影响的基本现象。经过几十年的研究，已经找到了精确的方法来解释最简单的原子和分子中的电子动力学，并阐明了在纯双电子系统中单个光子射出两个电子的影响。本计画的目标是研究具有两个以上电子的基本分子内的相关电子动力学。这项工作将推进理解这一过程的基础科学，目前在纯双电子分子中最完整，到化学相关物种，如乙烯和水。相关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。对具有两个以上电子的分子中电子相互关系的更全面的理解将产生更广泛的影响，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。涉及第二排原子的分子的双光离（DPI）是理论的长期目标，本工作旨在推进这些能力，特别是支持最近通过重合动量成像光谱（例如COLTRIMS）测量乙烯和水分子的双电离的实验观察，可以通过库仑爆炸后离子碎片的运动学完全重建来观察体-框架角分布。这两个分子靶标都提供了一个明显更复杂的分子，可以将新的理论计算与目前存在的H2水平的测量结果进行比较。光子从原子或分子中带走两个电子，必然需要对电子相关的正确描述，并作为这种现象的直接探测。以前用于研究最简单分子（H2和最近的Li2）中这一过程的双电离理论计算的发展和扩展将扩展到考虑多电子多原子分子作为目标，以便更好地理解包含第二排原子拥有更多电子的基本分子中电子相关的更广泛后果。更全面地理解和详细地描述高度相关电子动力学的影响，特别是在连续体中，是原子和分子物理研究界的长期目标。该奖项反映了美国国家科学基金会的法定使命，并通过使用基金会的知识价值和更广泛的影响审查标准进行评估，被认为值得支持。

Electron correlation is a fundamental phenomena which greatly impacts the behavior and structure of all matter. Many decades of research have led to accurate ways of accounting for the dynamics of electrons in the simplest atoms and molecules and have elucidated the impacts of ejecting two electrons by a single photon in purely two electron systems. The goal of this project is to examine the correlated electron dynamics within fundamental molecules with more than two electrons. This work will advance the basic science of understanding this process, which is currently most complete in purely two-electron molecules, to chemically relevant species, e.g. ethylene and water. 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 a more complete understanding of electron correlation in molecules with more than two electrons would impact many other fields of study, including chemistry, atomic and molecular physics, molecular biology, and material science. Double photoionization (DPI) of molecules involving second-row atoms is a long-term goal of theory and this work seeks to advance these capabilities, in particular to support recent experimental observations via coincidence momentum imaging spectroscopy (e.g., COLTRIMS) measuring the double ionization of ethylene and water molecules that can observe the body-frame angular distributions via a kinematically complete reconstruction of the ionic fragments after Coulomb explosion. Both molecular targets provide a significantly more complicated molecule to compare new theoretical calculations with these measurements at the level of what presently exists for H2. The removal of two electrons from an atom or molecule by photon(s) necessarily requires a correct description of electron correlation and serves as a direct probe of this phenomenon. The development and expansion of theoretical calculations dedicated to double ionization previously employed for studying this process in the simplest molecule, H2 and most recently Li2, will be expanded to consider multi-electron polyatomic molecules as targets, in order to better understand the broader consequences of electron correlation in fundamental molecules containing second-row atoms possessing many more electrons. A fuller understanding and detailed description of the effects of highly correlated electron dynamics, particularly in the continuum, is a long-term goal of the atomic and molecular physics research community.This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.