Universal nonsingular van der Waals potentials

Calculation of dispersion energies

We summarize the theory of van der Waals (dispersion) forces, with emphasis on recent microscopic approaches that permit the prediction of forces between solids and nanostructures right down to intimate contact and binding. Some connections are pointed out between microscopic theory and macroscopic Lifshitz theory.

First-principles theory of van der Waals forces between macroscopic bodies

We present a first-principles method for the determination of the van der Waals interactions for a collection of finite-sized macroscopic bodies. The method is based on fluctuational electrodynamics and a rigorous multiple-scattering method for the electromagnetic field. As such, the method takes fully into account retardation, many-body, multipolar, and near-fields effects. By application of the method to the case of two metallic nanoparticles, we demonstrate the breakdown of the standard 1/r(2) distance law as the van der Waals force decays exponentially with distance when the nanoparticles are too close or too far apart.

Equilibrium adsorption on single and aggregated nanospheres

The mean field density functional theory has been used to explore Ar adsorption onto single and double identical carbon dioxide nanospheres. We have studied adsorption from subsaturation up to saturation at several temperatures. For the single sphere case, the adsorption excesses and density profiles approach those of plane cases as the spherical substrate size increases; at each temperature, the transition from thin-film to thick-film adsorption is strongly dependent on the size of substrate and the adsorption behavior approaches to that of a plane when the substrate size goes to a large value. For the double sphere case, the cluster formed within the region analogous to the pendular region formed by two contacting identical nanospheres of radius of 1.7 nm has also been studied. The two sphere structure favorites the cluster forming in the interstitial region but does not affect the adsorption transition.

Nonsingular van der Waals Potential and Its Contributions to Gravitational Coagulation

The coagulation and the stability of dilute colloids at high Péclet number were studied in consideration of the universal nonsingular van der Waals interactions recently developed by J. X. Lu and W. H. Marlow (1995, Phys. Rev. Lett. 74, 1724). The capture efficiency of gravitational coagulation of uncharged colloids was found to be diminished due to the effect of finite molecular size (EFMS). The gravitational coagulation stability diagram of charged colloids was also found to be shifted when the gravitational convection was much stronger than the Brownian diffusion. Copyright 2001 Academic Press.