DNA solitons with realistic parameter values

Self-cohering, localized excitations of a DNA polymer chain are predicted using elastic parameter values that correspond well with established data. This ‘‘soliton’’ is constructed out of hydrogen-bond-stretching optical phonons and transverse-acoustic shearing waves. Numerical integration of model equations of motion shows a clear transformation from dispersive packets at low amplitude to solitonlike states at higher amplitude. Minimum excitation energies are estimated in the range of 0.1 eV.