Molecular Polarizabilities in Aqueous Systems from First-Principles.

We discuss the results of first-principles calculations of molecular polarizabilities in condensed systems composed of well-defined building blocks, with a focus on water and simple aqueous solutions. We show that molecular polarizabilities are subtle fingerprints of structural changes induced in liquid water by the environment, e.g., the presence of ions and confined media, as well as by temperature and pressure. We also point out the importance of molecular polarizabilities in the calculation and interpretation of specific vibrational signatures of aqueous systems, notably Raman and sum-frequency generation spectra.