Molecular dynamics study of hydrated imogolite. 2. Structure and dynamics of confined water.

The behaviour of water confined in an imogolite nanotube was studied by means of molecular dynamics simulations. The results of the study show an important difference between the interaction of water molecules with the internal and external surfaces of the nanotube. The analysis of the density profiles of confined molecules, of their spatial organisation, of the size of molecular clusters, of the lifetime of H-bonds in the system and of dynamical characteristics of molecules permits us to qualify the external imogolite surface as hydrophobic, whereas the internal surface reveals a hydrophilic character.