New Insights into the Structure of Water with Ultrafast Probes

How water molecules interact with their neighbors--the "structure" of water--has long been a matter of intense experimental and theoretical interest. In their Perspective, Zubavicus and Grunze discuss results on water structure reported in the same issue by Wernet et al. and in a recent issue by Ruan et al. obtained with ultrafast time-resolved techniques. By heating a layer of ice with subpicosecond infrared pulses, and then using ultrafast electron diffraction, Ruan et al. were able to follow the melting and restructuring of the ice layer. Wernet et al. used x-ray absorption and Raman scattering to measure the instantaneous electronic structure of oxygen atoms in water. The new results should provide a rich source of data for computer simulations of water's structure