US-Norway Cooperative Research: Investigation of Core- ionization Energies, Acidities and Related Chemical Properties

该奖项支持俄勒冈州立大学的T·达拉·托马斯教授和劳伦斯·伯克利实验室的米歇尔·R·西格尔博士与挪威特罗姆索大学化学系的莱夫·J·赛瑟尔教授进行的研究合作。他们都对了解影响分子接受电荷能力的因素感兴趣。他们正在研究核电离能、质子亲和力和加成反应的速率和方向之间的关系。他们还将研究噻吩环中的取代基效应和非平面酰胺中的电荷分布。他们的研究使用了核心电离能和奥古尔动能的实验测量，这些能量彼此之间以及与气相酸度的比较，以及从头计算电子结构。这项研究的实验设备主要包括一台电子能谱仪，位于俄勒冈州立大学。所有三个地点都进行了一些理论工作，但理论能力和设施的主要焦点是特罗姆索大学。它有一套完善的理论程序，有效地利用这些程序的计算机，以及帮助开发对这些问题的进一步见解的理论化学家的核心。许多重要的化学过程依赖于分子接受电荷的能力。这种能力受到两个因素的影响：中性分子中的电荷分布和价电子在电荷添加后重新排列的能力。这项研究调查了长期以来被用来理解这些影响的简单模型的缺陷。它应该对小分子的电子结构和影响分子接受电荷能力的因素有更好的理解。

This award supports Professor T. Darrah Thomas of Oregon State University and Dr. Michele R. Siggel of Lawrence Berkeley Laboratory for research collaboration with Professor Leif J. Saethre of the Department of Chemistry of the University of Tromso, Norway. They share an interest in understanding the factors that affect the ability of a molecule to accept charge. They are studying the relationships between core-ionization energies, proton affinities, and the rates and orientations of additions reactions. They will also investigate substituent effects in thiopenes and the charge distri- bution in nonplanar amides. Their research uses experimental measurements of core-ionization energies and Augur kinetic energies, comparison of these energies with each other and with gas-phase acidities, and ab initio electronic structure calculations. The experimental facilities for the research, including primarily an electron spectrometer, are at Oregon State University. Some of the theoretical work is done at all three locations, but the main focus of theoretical capabilities and facilities is the University of Tromso. It has a well developed set of theoretical programs, computers for efficiently exploiting them, and a core of theoretical chemists to help in developing further insights into these problems. Many important chemical processes depend on the ability of a molecule to accept charge. This ability is affected by two factors: the charge distribution in the neutral molecule and the ability of valence electrons to rearrange after the charge is added. This research investigates the deficiencies of simple models that have long been used to understand these effects. It should produce a better understanding of the electronic structure of small molecules and of the factors that affect the ability of molecules to accept charge.