Microdynamics and phase equilibria in organic nanocrystals

The effects of confinement on various organic molecules have been studied by nuclear magnetic resonance (NMR) relaxation techniques (T2 and T1ρ) between room temperature and 77 K. Cyclohexane, pentadecane, squalane, and squalene have been constrained within 60 Å porous silica, and the behaviour of the resulting nanocrystals has been compared to that of the bulk material. In all cases the molecular dynamics of the confined material were found to be significantly different from the bulk, and there is evidence to suggest that the behaviour is largely dependent on the size and shape of the molecules and the resultant structural disorder present when constrained within the pores.