Exchange Coupling in Transition Metal Polyhydrides

9411030华盛顿大学海因基博士，华盛顿大学化学系，由无机化学、生物无机化学和金属有机化学项目支持，研究发生在聚氢化物金属络合物中的高温成对质子隧穿。将制备一系列新的多种金属的二氢化物和聚氢化物。通过改变金属和辅助配体，可以得到稳定的二氢、二氢-氢化物和多氢化合物，显示出大的氢-氢自旋偶联。对发生在这些络合物中的耦合的温度依赖性的分析将揭示是否通过量子力学隧道机制发生氢交换。这项研究的很大一部分将涉及对氢化物的研究，其中已掺入了氚或氚。氚核磁共振将被用来表征其中一些系统的行为。氢分子可以通过允许它们与金属原子相互作用而被激活。这一行为具有巨大的实用价值，并在实验室和工业化学中用于提高氢发生许多反应的能力，包括几乎所有的“氢化”反应。一个具体的例子是不饱和脂肪转化为饱和脂肪的过程。另一方面，随着人们对氢作为清洁燃料的兴趣增加，氢与金属之间的相互作用已成为一个重要的话题。在这个项目中，将研究氢与金属结合的基本方式，并确定氢原子在金属影响下如何相互交换的细节。

9411030 Heinekey University of Washington Dr. Michael Heinekey, Chemistry Department, University of Washington, is supported by the Inorganic, Bioinorganic, and Organometallic Chemistry Program for the study of the high temperature pairwise proton tunnelling which occurs in polyhydride metal complexes. A series of new dihydride and polyhydride of a variety of metals will be prepared. By altering the metal and ancillary ligands stable dihydrogen, dihydrogen-hydride, and polyhydride complexes which show large hydrogen-hydrogen spin couplings will be obtained. An analysis of the temperature dependency of the couplings which occur in these complexes will reveal whether hydrogen exchange occurs by a quantum mechanical tunnelling mechanism. A significant portion of the study will involve the study of hydrides into which deuterium or tritium has been incorporated. Tritium nmr will be used to characterize the behavior of some of these systems. Hydrogen molecules may be activated by allowing them to interact with metal atoms. This behavior has tremendous utility and used in laboratory and industrial chemistry to increase the ability of hydrogen to undergo many reactions, including virtually all "hydrogenation" reactions. One specific example is the process in which unsaturated fats are converted into saturated ones. In another respect, the interactions between hydrogen and metals has become an important topic with the increased interest in hydrogen as a clean fuel. In this project the fundamental ways in which hydrogen becomes attached to a metal will be investigated and the details of how hydrogen atoms interchange with each other under the influence of a metal will be determined.