Cavitation contribution

It is important to note at this point the quantitative effect on the energy surfaces of solute-solvent interactions. As already anticipated, the dominant effect is due to electrostatic polarization in fact, in the range of distances of Fig. 3, the fluctuations of dispersion, repulsion and cavitation contributions are respectively 0.3 kcal/mol, 1.1 kcal/mol and 0.9 kcal/mol, which must be compared with 100 kcal/mol, the order of magnitude of variation of polarization in this case. 

The cavitation contribution is determined following Pierotti s scaled particle theory, where AGcav is expressed as an expansion series in powers of the radius of the sphere which excludes the centers of the solute molecules from the solute, Rms (i.e., the sum of the solute and solvent radii Eq. 4-6). The expansion coefficients Kt (i = 0-3) are expressed in terms of properties of the solvent (the radius of the solvent molecule and the numeral density) and of the solution (temperature and pressure) ... 

Fig. 34 Cavitational contribution, eC3V/e, of the overall deformation between 0.0001 and 1 ms-1 (i.e. at strain rates from 0.001 to 10s 1) for a -nucleated PP tested at room temperature (MFR 12 dgmin 1) and for its non-nucleated homologue...

Colominas, C., Luque, F.)., Teixidd,)., and Orozco, M. (1999). Cavitation contribution to the free energy of solvation. Comparison of different formalisms in the context of MST calculations, Chem. Phys. 240, pp. 253-264. 

The resulting physical model of an insonated electrode can he described as a steady diffusion layer a few microns thick brought about by acoustic streaming, which is occasionally and randomly punctuated by a cavitational event the frequency and violence of which is dependent on the solvent and ultrasound intensity. At high intensity and short horn to electrode separation, the cavitational contribution becomes substantial with violent cavitational activity giving a pronounced deviation from the steady diffusion layer model. 

Each of these types of molecular surfaces is adequate for some applications. The van der Waals surface is widely used in graphic displays. However, for the representation of the solute cavity in a continuum model the Accessible and the Excluding molecular surfaces are the adequate models as long as they take into account solvent. The main relative difference between both molecular surface models appears when one considers the separation of two cavities in a continuum model and more precisely the cavitation contribution to the potential of mean force associated with this process (Figure 2.1.6). In fact, we have shown that only using the Excluding surface the correct shape of the potential of mean force is obtained. The cavitation term cannot be correctly represented by interactions among only one center by solvent molecule, such as the construction of the Accessible... 

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