Optical and Microwave-Molecular Beam Studies of Transient Chemical Compounds

在化学学部实验物理化学项目中，将使用激光和微波分子束光谱技术(1)获得Sc、Ag和Pt过渡金属团簇及其氢化物和碳化物的旋转常数、超精细常数和永久电偶极矩；(2)研究CH的预解离；(3)通过测量质子磁超细常数来研究MgOH中的振动问题。第一项研究为从头计算提供了测试，而第二项研究是检验在避免交叉中混合的两种状态的性质的一种方法。由于状态的电子特征不同，斯塔克位移提供了一些信息，可以用来推断能级的混合集。在第三个问题中，观测到的常数可以提供势能面形状的信息。本研究的目的是简化光谱，以便研究极短（瞬态）气相物质的动力学和结构。将研究一些含有过渡金属的非常基本的化学物质中的化学键。对这种键的理解在表面科学和无机化学中是很重要的，并且对催化也有影响。

In this project in the Experimental Physical Chemistry Program of the Chemistry Division, laser- and microwave-based molecular beam spectroscopic techniques will be used (1) to obtain rotational constants, hyperfine constants, and permanent electric dipole moments of transition metal clusters of Sc, Ag, and Pt and their hydrides and carbides; (2) to study the predissociation of CH; and (3) to study the vibronic problem in MgOH by measuring the proton magnetic hyperfine constants. The first study provides tests for ab initio calculations, while the second is a way of examining the nature of two states which become mixed in an avoided crossing. Since the states differ in their electronic character, the Stark shifts provide some information which can be used to deduce the mixing set of levels. In the third problem the observed constants can provide information about the potential energy surface shape. %%% The goal of this research is to simplify optical spectra in order to study the dynamics and structure of very short-lived (transient) gas phase species. The chemical bonding in some very fundamental chemical species containing transition metals will be investigated. An understanding of such bonding is important in surface science and inorganic chemistry, and has implications for catalysis.