Equilibrium size of large ring molecules

The equilibrium properties of isolated ring molecules were investigated using an off-lattice model with no excluded volume but with dynamics that preserve the topological class. Using an efficient set of long range moves, chains of more than 2000 monomers were studied. Despite the lack of any excluded volume interaction, the size of the chain scaled like that of a self-avoiding walk, as had been previously conjectured. However, this scaling was only seen for chains greater than 500 monomers.