The proposing team has a well established experience in the use of INS on samples containing molecular hydrogen. Our recent experimental results on various types of H2 clathrate hydrates, obtained on TOSCA, allowed investigating the quantum dynamics of the guest H2 molecules inside the host cage, as well as the phonon density of states of these ice-like lattices. Now this new proposal aims to study both the host and the lattice dynamics of clathrate hydrates of different structure and composition: (1) weakly hydrophobic guest hydrates containing H2S; (2) water-ammonia ternaries with tetrahydrofuran and hydrogen. From the TOSCA spectra it will be possible in former case to derive the rattling and the rotational dynamics of the H2S molecules inside the cages, while in the latter case to probe the pronounced effects of the strong H-bonds associated to the NH3 molecules in the host lattice.