Exchange Coupling in Transition Metal Polyhydrides

在无机、生物无机和有机金属化学项目的支持下，华盛顿大学的Michael Heinekey博士将继续研究一种新的量子力学过程，该过程涉及在某些过渡金属多氢化物配合物中高温下质子的双向隧穿。这一过程导致这些配合物的核磁共振（NMR）光谱中的质子-质子耦合常数异常大。这种新现象的范围将由合成额外的多氢化物配合物与不同的过渡金属和各种配体除了氢。隧穿过程的详细机制将通过非弹性中子散射、中子衍射和核磁共振波谱来研究，特别强调氚核磁共振波谱。某些有机金属氢化物中的氢原子对交换位置而不破坏金属-氢键。有机金属氢化物是一类重要的工业催化剂，该项目有望有助于更好地了解催化作用的机理。

With the support of the Inorganic, Bioinorganic and Organometallic Chemistry Program, Dr. D. Michael Heinekey of the University of Washington will continue his investigations of a new quantum mechanical process involving pairwise tunnelling of protons at high temperatures in certain transition metal polyhydride complexes. This proceess leads to exceptionally large proton-proton coupling constants in the nuclear magnetic resonance (NMR) spectra of these complexes. The scope of this novel phenomenon will be defined by the synthesis of additional polyhydride complexes with different transition metals and a variety of ligands in addition to hydrogen. The detailed mechanism of the tunnelling process will be investigated using inelastic neutron scattering, structure determination by neutron diffraction, and NMR spectroscopy, with particular emphasis on tritium NMR spectroscopy. %%% Pairs of hydrogen atoms in certain organometallic hydrides exchange positions without breaking the metal-hydrogen bonds. Organometallic hydrides constitute an important class of industrial catalysts, and this project is expected to help provide a better understanding of the mechanism of catalytic action.