Microscopic approach of Hamaker between spherical particles

3 Microscopic approach of Hamaker between spherical particles 

For two spheres having the same radii (ffi = R2), Equation (540) simplifies to 

If there are two spheres of equal radius, HSph, then the interaction potential can be calculated as half the value of the sphere-surface interaction potential given by Equation (538) 

We may also obtain Equation (544) by inserting (Rl = R2) into Equation (543) for two spheres having the same radius. On the other hand, for the rarely encountered (D RSph) case, for two spheres having the same radius (Rl = R2), which are far apart, it was calculated that 

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