Enhanced cohesion of matter on a cylindrical surface February 1 , 2008

We evaluate the cohesive energies E b of four systems in which particles move on a cylindrical surface, at fixed distance R from the axis. We find quite nonuniversal dependences of E b on R. For the Coulomb binding problem, E b is a monotonically decreasing function of R. For three problems involving Lennard-Jones interactions, the behavior is nonmonotonic; E b is larger at R = ∞ than at R=0; the maximum binding corresponds to R ∼ 0.7 σ (the hard core parameter). Consequences of the enhanced binding are discussed. The discovery of carbon nanotubes has stimulated a rapid evolution of ideas, experiments and understanding concerning states of matter confined to the proximity of a cylindrical surface[1, 2, 3]. Examples of such systems include electrons present within a nanotube and atoms or molecules moving just outside or within such tubes. This paper reports unexpected behavior we have found in studies of four such systems: a +/− pair of charges bound by 1