θ Region of a Polymer Chain

Exact enumeration methods have been used in the study of the self-interacting, self-avoiding lattice walk model of a polymer chain, with particular emphasis on the θ point at which the effects of interaction and volume exclusion are supposed to cancel. θ temperature estimates for short chains computed from the partition function and the moments of the end-point separation have been extrapolated to infinite chain length. The extrapolated results, some of which fail to converge satisfactorily, do not point to the existence of a unique θ point, but suggest a relatively broad range θ of temperatures.