Torsion solitons in linear macromolecules

A phenomenological model for the dynamics of localized (soliton-like) torsi on waves in linear macromolecules is considered. It is shown that the anhar monicity of the torsion potential, which characterizes deceleration of rota tion of the chain units about a valence bond, can result in the appearance of torsion solitons with a finite supersonic velocity spectrum. The soliton s are dynamically stable. They retain their shape in the course of motion, which is not accompanied by phonon radiation. Interaction of solitons is in elastic, Collision of solitons always gives rise to phonon radiation, which becomes especially noticeable near the upper boundary of the velocity spec trum. The existence of torsion solitons should be expected in linear macrom olecules that take a three-dimensional helical conformation in the ground s tate. In macromolecules adopting a flat zigzag conformation, the conditions necessary for the soliton existence are considerably more severe.