Just another WordPress site - Ruhr-Universität Bochum

We present computer simulation results for the spectra of collective quantities of hydrogen bonded systems which present a different degree of hydrogen bond strength. The present analysis allows to clarify which are the features connected with the presence of a structural arrangement of molecules induced by the hydrogen bonding. Localized motion is found to be reflected in the appearance of extra peaks in the spectra besides the one related to the acoustic like propagation of density fluctuations. The nature of these modes is discussed taking into account recent investigations performed through an instantaneous normal mode analysis. For very weakly hydrogen bonded systems (e.g. hydrogen chloride) the spectral behaviour is found to be much more similar to that of simple monatomic liquids.