Molecular mobility and the structure of polar liquids

Self-diffusion coefficients of different classes of polar solvents are measured by the proton spin echo method in the temperature range of 288–318 K. In the same temperature range viscosities and dielectric relaxation times of the liquids under study are measured or taken from the literature and the activation energies of self-diffusion processes, viscous flow, and dielectric relaxation are calculated. The results obtained are compared with the literature data on structural relaxation times in the studied solvents and the conclusion is drawn about the role of the spatial hydrogen bond network in the mobility of molecules forming this network.