Chechko V. Peculiarities of anomalous light scattering in solutions with strong hydrogen bonds

The Thesis is devoted to the study of the anomalous low-concentration maximum in the integral intensity of molecular light scattering in dilute aqueous solutions of glycol and glycerol. The analysis of results obtained by methods of the correlation spectroscopy (dynamical light scattering) and molecular light scattering allows to state that complex structural changes take place in solutions in vicinity of maxima observed. The hydrodynamic radii of optical microinhomogeneities were determined by the method of correlation spectroscopy. It is shown that maximal hydrodynamic sizes for aqueous solutions of glycerol correspond to concentrations of anomalous light scattering and they reach 80A although the size of an elementary cluster is about 10A. The comparison of the temperature and concentration dependencies of characteristic sizes of microinhomogeneities, the intensity of light scattering and its depolarization coefficient forces us to conclude that cooperative groups of elementary clusters are responsible for all anomalies observed. It is shown, that the relaxation to the equilibrium state for solutions with strong H-bonds is very slow (about one day and more. At that, complicated energetic, polarization and angular characteristics are observed and their do not depend principally on an initial state of solution and a method of its preparation. Due to this the inconsistency of experimental data of different authors is explained. The cluster approach to the description of anomalous light scattering in solutions with strong H-bonds is proposed. It reproduces all essential temperature and concentration regularities in the behavior of molecular light scattering.