Statistical mechanics of interacting peapods

We evaluate the equation of state of the quasi-one-dimensional (1D) phase of ${\mathrm{C}}_{60}$ molecules in small carbon nanotubes, nicknamed peapods. The chemical potential and 1D pressure are evaluated as functions of the temperature and density, initially with the approximation of nearest-neighbor interactions and classical statistical mechanics. Quantum corrections and long-range interaction corrections are discussed, as are the effects of interactions with neighboring peapods. Transition phenomena involving the 3D coupling are evaluated.