The proposing team has a well established experience in the use of neutron scattering on samples containing molecular hydrogen. Our recent experimental results on standard sII and sH hydrogen-filled clathrate hydrates, obtained on TOSCA, allowed to investigate the quantum dynamics of guest H2 molecules inside the host cages, as well as the lattice dynamics of these water cages. This proposal aims to study a new compound (i.e. a proton-ordered sII binary clathrate hydrate) still formed by H2, water and perdeuterated THF, but having a fully ordered protonic structure, analogous to ice XI with respect to ice Ih. From the neutron spectra it will be possible to derive the dynamics of the single H2 molecule inside the small cages of a proton-ordered sII clathrate hydrate, as well as to extract the H-projected density of phonon states of the lattice formed by the proton-ordered host cages.