COLLISIONS OF SOLITONS IN POLYACETYLENE

The dynamics of collisions of structural defects in polyacetylene are studied numerically using the Su-Schrieffer-Heeger model extended to i nclude the influence of an external electric field. The electric field is used to accelerate charged solitons in polyacetylene and it is int roduced in terms of a time-dependent vector potential. Collisions betw een solitons with different charges in a soliton network are considere d. It is found that although two isolated solitons on a chain may exch ange their moments in a collision, several solitons work like a barrie r attenuating the transfer moment. A charge oscillation is observed be tween the colliding solitons and partial charge transfers. It is also found that if the colliding solitons hold different charges (charged s oliton-charged soliton or neutral soliton-charged soliton), the pair i s more stable, surviving the collision. Neutral solitons are unstable against collisions and make a dynamic bound state. The energies involv ed are also discussed. (C) 1997 Elsevier Science B.V.