Certain possible conformations states of a uniform elastic polymer chain

A uniform elastic macromolecule is considered-the so-called persistent model. The possible appearance in it of a dense globular state with nematic ordering of the elements of the chain is analysed. The entropy of such a system in an arbitrary state is calculated. It is shown that the relatively short and rigid chain forms a toroidal structure. On elongation of the chain the torus increases without changing proportions proper. With change in the parameter the toroidal structure may be converted to the usual single linkage one. The possibility of applying the model considered to the problem of the three-dimensional packing of nucleic acid is briefly discussed.