Hydrogen bonding in supercritical water confined in carbon nanotubes

We present molecular dynamics results on the hydrogen bond structure of water at supercritical conditions adsorbed inside carbon nanotubes (CN). Water was described by means of a flexible version of the simple point charge potential and the water–tube interaction was of the Lennard-Jones type. We found significative reductions in the average number of hydrogen bonds for all considered tubes with respect to bulk water. This effect is much more important than for confined water at ambient conditions.