A one-dimensional model for hydrogen-bonded chains is investigated by including inhomogeneities (impurities) produced by changing parameters of the hydrogen as well as oxygen subsystems. The soliton scattering by a local impurity is studied analytically in the framework of the collective-coordinate approach, and the effective potential describing such an interaction is derived. The threshold velocity, which corresponds to the soliton repulsion by the impurity, is calculated. It is demonstrated that the soliton scattering produces an emission, mostly in the oxygen subsystem. Due to the emission the velocity of the soliton decreases, and it may be trapped by an attractive impurity. We also calculate the threshold velocity for such an effect. The decay of the soliton transmission coefficient in a disordered hydrogen-bonded system is analyzed using the independent-scattering approach.

• Received 8 October 1990

DOI:https://doi.org/10.1103/PhysRevA.43.3117