DIELECTRIC SCREENING AND PHONON-DISPERSION IN METALLIC GLASSES

Expressions for the phonon frequencies of the binary and ternary metal lic glasses are derived on the basis of various dielectric screenings. A model which assumes a central force, effective between nearest neig hbours, and a volume dependent force is adopted. The phonon frequencie s of longitudinal and transverse phonons for the binary metallic glass es Ca70Mg30, Mg70Zn30, and Cu57Zr43 and for the ternary metallic glass Pd77.5Si16.5Cu6 are computed. The theoretical results compared with e xperimental data underline the importance of dielectric screening by c onduction electrons.