The behaviour of clathrate hydrates in the THz region could provide useful information about inclusion compounds. In this study, terahertz time-domain spectroscopy (THz-TDS) revealed the dynamics of gaseous guest molecules inside the water framework of a clathrate hydrate. Distinct footprints of each gaseous molecule (CH4, H2 and O2) inside the gas hydrate lattice were analysed. Thermally stimulated gas hydrates give out gas molecules (secondary guests) to remain secure, and each gas has a specific degassing temperature. In this way, they form the stable sII THF hydrate with empty small cages (512) which can survive at temperatures up to 278 K.
