NMR studies of the dynamics of HD adsorbed in MCM-41

The motion of hydrogen deuteride molecules adsorbed on MCM-41 at monolayer coverages has been explored using NMR techniques. The nuclear spin-spin and nuclear spin-lattice relaxation times show an abrupt change at 8.8 K, consistent with the formation of small clusters below that temperature. The molecular tunneling times deduced from the NMR measurements are consistent with the values determined by neutron scattering [Coulomb et al., Micro Meso Matls 101,270 (2007)].