Milton W. Cole

Path integral study of the 4He wetting transition

The4He wetting transition on a Cs surface is for the first time studied by Path Integral Monte Carlo simulation. Numerical results for a system of 644He atoms are qualitatively consistent with a wetting transition at a temperature T ∼ 2 K.

Adsorbed Gases in Bundles of Carbon Nanotubes

The discovery of carbon nanotubes [1, 2] has led to extensive investigation of adsorption on these remarkable substrates. Much of this effort has been directed toward potential applications, such as gas storage and separation, which exploit the fact that every carbon atom of a single-wall carbon nanotube (SWNT) can provide two surfaces, inside and outside of the tube, for potential gas adsorption; this corresponds to a specific area of order 2500 m 2 /g Early claims of extraordinary hydrogen uptake (e.g., six H 2 , molecules per C atom) stimulated a particularly intense effort to achieve practical amounts for storage applications, but those results have not been confirmed by any subsequent experiments. More modest uptake (0.5 molecule per C atom) of H 2 has been found to occur in some experiments and that may suffice for storage and other applications [3-9].