Influence of quenching on low-frequency neutron and Raman spectra of glasses

Quenched and annealed samples of g-As₂S₃ are investigated by the low-energy Raman and inelastic neutron scattering and by diffraction of neutrons. The structure modifications caused by quenching lead to significant changes only of the low-frequency part of the vibrational spectrum: the density of vibrational states g(E) and the light to vibrations coupling constant C(E) increase uniformly along the spectrum in the energy interval 2<E<12 meV. The relative changes are the same both for g(E) and C(E) and are equal to 8%. Similarly the structure factor S(q) demonstrates a sufficient (15%) increase of the amplitude of the first sharp diffraction peak (FSDP) after quenching and negligible small changes of the main peaks. Uniformity of the relative changes of g(E) and C(E) along the acoustical spectrum probably means that these changes are caused by the changes of sound velocity and density as a result of quenching.