The mechanisms and rates of interstitial H2 diffusion in crystalline C60 were studied. It was observed that the isolated interstitial H2 molecules bind preferentially in the lattice octahedral (O) sites and diffuse by hopping between O and tetrahedral sites. The results showed that the events involving dimers greatly enhance the self-diffusion rates of interstitial H2 in face-centered cubic C60.

Mechanisms and Rates of Interstitial H2 Diffusion in Crystalline C60. Uberuaga, B.P., Voter, A.F., Sieber, K.K., Sholl, D.S.: Physical Review Letters, 2003, 91[10], 105901