title: Ground state and thermal properties of a lattice gas on a cylindrical surface.
abstract: Adsorbed gases within, or outside of, carbon nanotubes may be analyzed with an approximate model of adsorption on lattice sites situated on a cylindrical surface. Using this model, the ground state energies of alternative lattice structures are calculated, assuming Lennard-Jones pair interactions between the particles. The resulting energy and equilibrium structure are nonanalytic functions of radius (R) because of commensuration effects associated with the cylindrical geometry. Specifically, as R varies, structural transitions occur between configurations differing in the "ring number," defined as the number of atoms located at a common value of the longitudinal coordinate (z). The thermodynamic behavior of this system is evaluated at finite temperatures, using a Hamiltonian with nearest-neighbor interactions. The resulting specific heat bears a qualitative resemblance to that of the one-dimensional Ising model.
authors.affiliation: Department of Physics, Pennsylvania State University, University Park, PA 16802, USA.
authors.forename: M Mercedes
authors.initials: MM
authors.lastname: Calbi
authors.forename: Silvina M
authors.initials: SM
authors.lastname: Gatica
authors.forename: Mary J
authors.initials: MJ
authors.lastname: Bojan
authors.forename: Milton W
authors.initials: MW
authors.lastname: Cole