Electronic Theory of Simple Chemical Reactions

这个项目属于化学系的理论与计算化学项目，涉及计算量子化学的两个不同但相关的进展。首先是基于自然轨道的构型相互作用方法的扩展、测试和标定。第二是应用理论方法来回答一些重要的分子结构问题。所研究的体系包括氨二聚体、三原子卤素自由基、环烯（七个六边形围绕着一个七边形的碳氢化合物）和环羰基阳离子。现代高速计算机可用于计算分子的形状和能量，包括那些尚未被合成的分子。在这项研究中，不仅进行这些计算的计算机方法得到了进步，而且它们也被应用于研究外来分子，例如由三个氯原子组成的分子，而不是像我们更熟悉的氯分子那样由两个原子组成。

This project in the Theoretical and Computational Chemistry Program of the Division of Chemistry involves two distinct but related advances in computational quantum chemistry. The first is the extension, testing, and calibration of a configuration-interaction method based on natural orbitals. The second is the application of the theoretical methods to answer a number of important molecular structural questions. The systems being studied include the ammonia dimer, triatomic halogen radicals, circulenes (hydrocarbons with seven hexagons surrounding a heptagon), and the cyclocarbinyl cation. %%% Modern high-speed computers can be used to calculate the shapes and energies of molecules, including those which have not as yet been synthesized. In this study not only are the computer methods for carrying out these calculations being advanced, but they are also being applied to the study of exotic molecules such as that formed by three chlorine atoms rather than by two atoms as in the more familiar chlorine molecule.