Computer design solvent systems

Computer assisted solvent system design 64 6.2.3 Tropospheric ozone formation 108... 

In order to determine if a correlation exists between Ito s classification and the values of the previous theoretical parameters, the 15 solvent systems used for the design of the classification have been studied. The values of interfacial tension, of densities, and of dynamic viscosities of the solvent systems were used to compute the values of the capillary wavelength and the settling velocities. The values of the three theoretical parameters have allowed to set ranges within which a solvent system is named hydrophobic, intermediate, or hydrophilic. The main interest is that the knowledge of some physical parameters of the solvent systems allows one to know, before any experiments, the best combinations for the greatest stationary-phase retenion. 

The diffusive behavior of a particle can be modeled using the Langevin equation. For example, in certain reactions, the two reactants must come into contact in order for a reaction to take place. In these types of reactions the rate-determining step may be due to the diffusion of the two reactants in the solvent. Computer simulations, commonly known as Brownian dynamics simulations, are employed at th molecular level to study these diffusion-controlled processes and aid in design of systems with prescribed transport or kinetic properties. 

We have seen how a seemingly simple reaction, the Kemp ehmination, fueled research about the effect of the medium around the catalytic base and the benzisoxazole ring. The medium evolved from simple solvents to more complex structures such as synzymes and finally culminated in proteins, natural, engineered, or computationally designed. In many of these cases, an increase in the catalytic power of the system was achieved through engineering a destabilizing (hydrophobic) environment around the transition state of the... 

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