  We analyze typical models which intend to describe (parts of) the dynamics of
H-Bonds in DNA. We show that these models generically allow for nonlinear
localized excitatons (NLEs) (discrete breathers). We especially study the
scattering of phonons by NLEs and observe strong reflection of phonons by the
NLE. We relate our results to the problem of functioning of a complex
biomolecule, e.g. the DNA.
