Hydrogen-bond dynamics in solution

In an intense interplay between experiment and theory, the mechanism for H-bond dynamics has been determined by the combination of IR experiments and molecular dynamics simulations. We have studied NaClO4(aq) since spectral features in the stretching region of this system show two distinct transient locally heterogeneous structures. The time-scales for inter-conversion of the local structures can be accessed through their spectral finger-print, In 2D Infra-red correlation spectroscopy, the exchange show up are off-diagonal intensity.

The spectral features correspond to OH groups in water molecules in distinct sub-shells within the first hydration shell of the anions, and the exchange involve both large angular reorientations of the water molecules and reorientational motion of the perchlorate anion.