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Ground state and thermal properties of a lattice gas on a cylindrical surface

M. Mercedes Calbi·Silvina M. Gatica·Mary J. Bojan·Milton W. Cole
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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.

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M. Mercedes Calbi, Silvina M. Gatica, Mary J. Bojan, Milton W. Cole. 2002-09-25. Ground state and thermal properties of a lattice gas on a cylindrical surface. https://arxiv.org/abs/cond-mat/0209220

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