Cavity energy

In (2.105), the assumption of the proportionality of solvent-accessible surface and cavity energy is explicitly shown, and therefore ak depends on the type of the k-atom interacting with the solvent. Ak(p ) is the complex function describing the solvent accessible surface area, and depends on p, which is defined by the following expression ... 

When a solute molecule is introduced into a condensed medium, the medium expends cavity energy, because it first forms a cavity to accommodate the guest solute molecule by increasing its volume equal to the volume of the solute molecule, as shown in Figure 7.8 a. This cavity energy is an additional energy. 

The effects of scale on the cavity sweepout process is somewhat unclear. However, due to the similarity of the sweepout fraction and hydrogen production data between the ANL and SNL tests, it can be inferred that the efficiency of the cavity energy transfer process is roughly scale independent. Therefore, the measured containment loads in the inerted tests were similar. 

The energy of an elastic wave in a solid is quantized just as the energy of an electromagnetic wave in a cavity. 

Kirkwood generalized the Onsager reaction field method to arbitrary charge distributions and, for a spherical cavity, obtained the Gibbs free energy of solvation in tenns of a miiltipole expansion of the electrostatic field generated by the charge distribution [12, 1 3]... 

Microwaves from the waveguide are coupled into the resonator by means of a small coupling hole in the cavity wall, called the iris. An adjustable dielectric screw (usually machined from Teflon) with a metal tip adjacent to the iris pennits optimal impedance matching of the cavity to the waveguide for a variety of samples with different dielectric properties. With an appropriate iris setting the energy transmission into the cavity is a maximum and simultaneously reflections are minimized. The optimal adjustment of the iris screw depends on the nature of the sample and is found empirically. 

Attard P 1993 Simulation of the chemical potential and the cavity free energy of dense hard-sphere fluids J. Chem. Phys. 98 2225-31... 

In this relationship. S is alkane solubility, A is the cavity surface area and a is the hydrophobic free energy per unit area. Extensive fitting of this equation [24] yields a value of 88 kJ mol A for the proportionality constant a. This value corresponds to an unfavourable free energy of about 3.6 kJ mol for the transfer of a CH2 group to aqueous solution. 

Fig. 6. Free energies of hydration calculated, for a series of polar and non-polar solute molecules by extrapolating using (3) from a 1.6 ns trajectory of a softcore cavity in water plotted against values obtained using Thermodynamic Integration. The solid line indicates an ideal one-to-one correspondence. The broken line is a line of best fit through the calculated points.

IS added to the short-range molecule-molecule interaction. Problems with the reaction ethod may arise from discontinuities in the energy and/or force when the number of les j rvithin the cavity of the molecule i changes. These problems can be avoided by dng a switching function for molecules that are near the reaction field boundary. 

An early application of the free energy perturbation method was the determination of t] tree energy required to create a cavity in a solvent. Postma, Berendsen and Haak determin the free energy to create a cavity (A = 1) in pure water (A = 0) using isothermal-isobai... 

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