Dynamical Structure Factor of Amorphous Germanium

Abstract

The dynamical structure factor of highly ordered and disordered states of amorphous Ge has been obtained from inelastic-neutron-scattering measurements. The results indicate significant changes in the phonon density of states, due to bond-angle-distribution variations. The modified structure factor, $G(Q,E)\mathrm{}$, indicates damped oscillatory behavior that is in very good agreement with the bond-coherency model of Weaire and Alben. Low-$Q$ deviations suggest coherency effects beyond first neighbors.