Hydration computational studies

The high reactivity of bay-region (and fjord-region) diol epoxides has intrigued chemists for years. Numerous experimental and computational studies have been carried out, affording a wealth of information on the mechanisms by which bay-region diol epoxides form adducts with nucleic acids and are deactivated by reaction with protective nucleophiles or by hydrolysis. Indeed, the hydration of diol epoxides forms unreactive tetrahydroxy metabolites known as tetrols (10.39, Fig. 10.14,a). 

Fig. 23.12. Results of computer studies simulating the hydration of amino acids, (top) self-bridging loops of hydrogen-bonded water molecules around alanine (center) polar bridging chains between polar solute atoms of threonine (bottom) water networks associated with the apolar groups of leucine [847]...

The microsolvation computations °° ° are excellent models of, for example, small hydrated clusters that can be observed in the gas phase. ° ° Still under intense computational study is how informative microsolvation computations are for understanding true solution phase chemistry. 

As in the case of aqueous solutions of electrolytes, computer studies have shed much light on the behaviour of aqueous solutions of non-polar and apolar molecules. They can give information on solute-solvent and solvent-solvent interactions in such solutions. This is a powerful tool for studying hydrophobic phenomena and is limited only by the accuracy of the assumed model and the quantities relevant to this model which are fed into the computer simulations. Simulation is of particular importance in the solution chemistry of large macromolecules and polymers which are extremely difficult to study experimentally, especially in dilute solutions. They are likely to be a dominant feature of the future study of hydrophobic hydration. 

Anomeric effects in fluoro and trifluoromethyl piperidines a computational study of conformational preferences and hydration... 

Urban JJ, Tillman BG, Cronin WA (2006) Fluoroolefins as peptide mimetics a computational study of structure, charge distribution, hydration, and hydrogen bonding. J Phys Chem A 110(38) 11120-11129... 

Experimental and computational study of hydration reactions of aluminum oxide anion clusters ... 

For the application of molecular modeling methods discussed in Sec. II, we shall go over the computational studies achieved in two diffo-ent ways. First, we shall discuss structural studies in which the main result was the optimized structure of the clay minml, either in hydrated or dehydrated form. ThCTefore, the emphasis is on the clay mineral network structure instead of the interlayer or adsorbate structure (exchangeable ions, organic/inorganic compounds, or water). Next, we shall review the investigations in which the main inta-est was in the structure of the intCTlayer with respect to the (hydrophobic or hydrophilic) clay surface. This... 

One of the recent successes in computCT simulation of clay mina-al hydrates is that the structure of interlayer wate in toms of quantitatively obtainable content called total radial distributionfunction was achieved by both Monte Carlo simulations and neutron diffraction methods (111,112). The accuracy of the method and the predicting power of the molecular simulation of this complex solid-liquid interface was first confirmed for the intolayCT structure of 2 1 clay mineral smectite. Computational studies on the clay mina-al-water interface using quantum mechanics, molecular mechanics, Monte Carlo, and molecular dynamics simulations are summarized in Table 5. 

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