NATURE OF BACKGROUND SCATTERING IN RAMAN-SPECTRA OF MATERIALS CONTAINING HIGH-WAVE-NUMBER VIBRATIONS

A new interpretation for the often observed phenomenon of 'Raman backg round' is presented and discussed. It is shown that in many cases the appearance of the background for various materials (organic and inorga nic) is associated with the presence of high-wavenumber v(XH) vibratio ns. The nature of the observed broad band can be explained by strong a nharmonic interaction between high-wavenumber excitation and low-waven umber phonons. The results of theoretical evaluations are presented. U sing the approach proposed, a good description of the unusual spectral features for several materials has been achieved. (C) 1997 John Wiley & Sons, Ltd.