  An impact of kink-type solitons on infrared lattice vibrations is studied for
incommensurate Frenkel-Kontorova model. It is shown that the vibration of
particles involved into the kink formation is very similar to that in a gap
mode around the force constant defect. IR phonon mode intensity is found to
possess a universal dependence on the system parameters and the kink
concentration. It is argued that the giant IR peak observed in a number of
incommensurate charge density wave conductors can be explained in terms of
dynamic charge transfer stimulated by kinks.
