Modeling of supramolecular ordering in molecular liquids: Structure, physicochemical properties, and macroscopic manifestations.

The results of recent developments on modelling of supramolecular ordering and macroscopic properties of molecular liquids and mixtures are reviewed. The main attention is paid to the approach based on a generalized quasichemical association model for a set of thermodynamic, dielectric and optical properties of liquids and mixtures, selforganized by specific bonding. The hierarchy of theoretical models of molecular aggregates is considered. The nonideal mixture of molecular aggregates, polyvariant as regards structure and composition, is discussed. Interrelations between a set of the thermodynamic, dielectric, and optical properties of liquid systems, and the characteristics of quasichemical processes are presented. Some of the problems of a quasichemical approach for a thermodynamic description of internal processes in liquids have been outlined. Applications for thermodynamic functions of mixing, permittivity, coefficients of isotropic and anisotropic Rayleigh light scattering in molecular liquids and mixtures are considered. Aggregation in molecular liquids, including long range molecular correlations, is discussed in terms of the integral and differential parameters of aggregation. Macroscopic manifestations of supramolecular ordering in a set of the physicochemical properties of molecular liquids and mixtures are discussed. For the first time a unified approach for thermodynamic, dielectric and optical properties of molecular liquid systems, reflecting different molecular parameters, by this quasichemical method on the molecular-structural level has been realised. (C) 1998 Elsevier Science B.V. Ail rights reserved.