Thermal desorption of hydrogen from ammonia borane: unexpected role of homopolar B–H⋯H–B interactions

The solid-state structure of ammonia borane is held together by an intricate N–H⋯H–B proton–hydride bonding network. These intermolecular interactions have long been considered to mediate the release of hydrogen from this material. Here we reveal the silent but important role played by B–H⋯H–B interactions in the thermal decomposition of this leading hydrogen storage candidate.