Phonon Spectrometric Evaluation of the Solute-Solvent Interface in Solutions of Glycine and Its N-Methylated Derivatives.

From the perspective of O:H-O bond cooperativity, we analyzed the solute capability of transiting the O:H-O bond from the mode of ordinary water to the hydration state and its consequence on the solution viscosity and surface stress. Phonon spectrometric results suggest that glycine and its N-methyl derivatives strongly affect the surrounding solvent molecules through H ↔ H repulsion and dipolar polarization. The H ↔ H interproton repulsion disrupts the surface stress, and the polarization enhances the solution viscosity.