Ab initio calculations of the dynamics of some hydrogen storage materials, comparing inelastic neutron scattering spectra

The nature of the interaction of neutrons with matter, make neutrons an ideal tool for studying the structural and dynamical properties of materials. Because of their wavelength, thermal neutrons can also simultaneously measure structure and dynamics. In inelastic processes (spectroscopy) the scattering process conveys information on the dynamics across the Brillouin zone and it has no selection rules, unlike Raman and Infrared spectroscopy (IR) making the assignment of the spectra relatively straight-forward. The incoherent cross section of hydrogen is over 20 times larger than most chemical elements. This makes incoherent inelastic neutron spectroscopy a very powerful tool to observe the dynamics of hydrogen containing materials. We have used abinitio DFT calculations to study the dynamics of a host of hydrogen storing materials, from light metal hydrides to MOF's.