Hydride Complexes: The chemistry and current significance of covalent hydrogen compounds of transition metals are discussed

Hydride complexes of transition metals were virtually unknown 12 years ago, but they have now been found to lie at the root of many interesting catalytic chemical reactions, some of which were used in industry even before the unique properties of hydride complexes, which formed their basis, had been realized. This article surveys the history, preparations, important properties, and reactions of hydride complexes, surveys their part in important catalytic industrial processes, and speculates about their possible role in the biological fixation of nitrogen.