THEORY OF VIBRATIONAL EXCITATIONS IN METALLIC GLASSES

A general theory of vibrational excitations in metallic glasses based on a disclination model of the structure of solids with local icosahed ral symmetry is proposed. Application of the non-orthogonal plane wave representation allows the theory to single out diagonal terms in the Hamiltonian and terms describing scattering of these waves due to dens ity and force constant fluctuations and fluctuations in the topology o f the structure. The Dyson's equation for the Green's function is obta ined and solved. The total vibrational density of state is obtained an d the problem of low energy states is discussed. (C) 1998 Published by Elsevier Science B.V. All rights reserved.