Solvation Forces

Two surfaces in a solvent will experience an oscillatory force as they approach each other. At separation distances in which the molecules are closely packed, the

Fig. 8.4 Diagram showing molecules of a liquid confined between two parallel planes

Fig. 8.4 Diagram showing molecules of a liquid confined between two parallel planes

maximum points in Fig. 8.4, the density between the two surfaces is higher compared with the bulk. This situation which is entropically unfavorable results in a repulsive force between the two surfaces. On the other hand, at separation distances in which the molecules are disordered, the minimum points in Fig. 8.4, the density is less than that of bulk. An attractive force arises due to the difference in density between two sides of the planes.

The salvation force can be calculated by applying the contact theorem [36, 75]. Solvation force is often described by an exponential decaying cosine function. For two parallel planes the salvation force is f (x) = f0 cos (8.1)

"0

where f is the force per unit area, f0 is the force extrapolated to zero separation distance, x is the separation distance for the surfaces, d0 molecular cross-section or diameter and x0 is the characteristic decay length.

Renewable Energy Eco Friendly

Renewable Energy Eco Friendly

Renewable energy is energy that is generated from sunlight, rain, tides, geothermal heat and wind. These sources are naturally and constantly replenished, which is why they are deemed as renewable.

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