Homopolar dihydrogen bonding in main group hydrides: discovery, consequences, and applications.

This perspective describes the recent discovery and investigation of homopolar dihydrogen bonding, and focuses on the identification and characterisation of hydride-hydride interactions in compounds of the main group elements. A highlight of this programme has been an appreciation of the important role played by this interaction in the structural and thermochemical properties of these materials, and in the mechanisms through which they release hydrogen. A fuller understanding of this new class of H∙∙∙H interactions has also allowed us to explore their role in the supramolecular chemistry of hydrogen-rich compounds.