Our present concept of dopant-enabled gas mobility in the water lattice is further supported by the NMR results about gas dynamics in hydrate structures. Accordingly, Moudrakovski et al. reported the NMR evidence for the enhanced CO 2 dynamics in a mixed CO 2 /THF hydrate, in contrast to the reduced CO 2 dynamics in a mixed CO 2 /isobutane hydrate as compared to the baseline of a pure CO 2 hydrate. Moreover, Moudrakovski et al. indicated that the cage-to-cage exchange of CO 2 molecules was observed exclusively in the mixed CO 2 /THF hydrate, but not in the mixed CO 2 /isobutane hydrate or the pure CO 2 hydrate. These observations are fully in line with our concept of defect-enabled gas mobility in the water lattice. Further discussions are following. First, we discussed in previous section that THF molecules are H-bonding molecules. The resulting THF-water H-bonds induce defects in the water lattice and create open channels for facilitating the inter-cage hoping of CO 2 molecules in the mixed CO 2 /THF hydrate. In contrast, isobutane molecules are non-polar entities without H-bonding capability.