THz spectra and dynamics of aqueous solutions studied by the ultrafast optical Kerr effect

The nature and extent of the effects that hydrophilic and hydrophobic solutes have on the dynamics of water molecules continues to be an area of intense experimental and theoretical investigation. In this work, we use the ultrafast optical Kerr effect to measure the picosecond dynamics and THz Raman spectral densities of a series of aqueous solutions. The solutes studied are the hydrophilic urea and formamide and the hydrophobic trimethylamine N-oxide and tetramethylurea. Measurements are made as a function of concentration betwee