"What does the bottle matter?", provided the liquid inside retains its everlasting benefic properties… Alfred de Musset would be surprised to learn that his passionate citation might only be true provided the bottle is not too thin, and that the understanding of the physical properties of molecular phases confined at a nanometer scale has become, two centuries later, of worldwide interest.

Indeed, when the size of a nanometric container compares with the typical lengths that rule the bulk properties of a system at the molecular level, strong geometric restrictions may become prevailing. For instance, they can disrupt crystalline order, or inhibit putative cooperative relaxation processes in supercooled liquids.
The interaction energy at the overextended nanocontainer/fluid interface is also crucial. This surface interaction may shift phase transitions temperatures and affect the molecular mobility.
The situation is even more complex for anisotropic phases, which are expected to be sensitive to the dimensionality of the container as well.

A further effect, due to the morphology (irregularity) of the inner surface of the nano-container, has shown up in the case of confined liquid crystals and is related to the concept of frozen quenched disorder in confinement.

D. Morineau et al., ILL Annual Report 2006, p. 50-51