Supramolecular statistical effect

Since the original definition of supramolecular chemistry was coined by Lehn several corollaries have emerged. One that has risen to great importance is the idea of a dynamic combinatorial library of molecular components that self-sort to generate supramolecules with reactive termini which are then predisposed to form covalent bonds. The effects of weak interactions together with geometric and steric constraints lead to the formation of far fewer products than would be predicted by pure statistics. This development will be discussed in greater detail later. 

Such specifics of interaction between dipoles of H O, cations and anions mostly determine the structure of water solution. The simplest idea of it is provided by the statistical theory of diluted solutions of strong electrolytes proposed by Peter Joseph Debye (1884-1966) and Erich Armand Hiickel (1896-1980) in 1923. Under this theory ions are treated as rigid non-polarizable spheres separated by a uniform medium with high value of the dielectric constant. At that, structure of the solution is function of distances dipoles H O and ions. Depending on it, it is customary to distinguish molecular and supramolecular structure. Molecular structure is determined by a direct effect of ions on the orientation and mobility of water dipoles and is manifested first of all by the formation of hydrates. Supramolecular structure is caused by undisturbed interaction of H O molecules between each other (Figure 1.2). 

Solvation behavior can be effectively predicted using electronic structure methods coupled with solvation methods, for example, the combination of continuum solvation methods such as COSMO with DFT as implemented in DMoF of Accelrys Materials Studio. An attractive alternative is statistical-mechanical 3D-RISM-KH molecular theory of solvation that predicts, from the first principles, the solvation structure and thermodynamics of solvated macromolecules with full molecular detail at the level of molecular simulation. In particular, this is illustrated here on the adsorption of bitumen fragments on zeolite nanoparticles. Furthermore, we have shown that the self-consistent field combinations of the KS-DFT and the OFE method with 3D-RISM-KH can predict electronic and solvation structure, and properties of various macromolecules in solution in a wide range of solvent composition and thermodynamic conditions. This includes the electronic structure, geometry optimization, reaction modeling with transition states, spectroscopic properties, adsorption strength and arrangement, supramolecular self-assembly,"and other effects for macromolecular systems in pure solvents, solvent mixtures, electrolyte solutions, " ionic liquids, and simple and complex solvents confined in nanoporous materials. Currently, the self-consistent field KS-DFT/3D-RISM-KH multiscale method is available only in the ADF software. 

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