Lattice dynamics of HgSe and beta-HgS was studied by three independent
methods: IR reflectivity, Raman scattering and neutron scattering mea
surements. New interesting features, found in the spectra are explaine
d and analyzed in detail. In particular, the possible influence of the
isotope effects on the results of measurements mentioned above is dis
cussed. (C) 1998 Elsevier Science B.V. All rights reserved.