Dynamics of silver phosphate glasses by light and neutron scattering measurements

New Raman and neutron scattering data on (AgI)x(AgPO3)1-x at various temperatures and Agi concentrations (0.0 < x < 0.55) are compared to obtain the Raman coupling function C(ω) and, in particular, its low-frequency limit. This study indicates a strong variation in the dynamics with increasing AgI content. Moreover the direct comparison of the Raman and neutron scattering data indicates that, in the ω ↪ 0 limit, C(ω) extrapolates to a non-vanishing value, giving interesting indications on the nature of the vibrational modes in disordered systems.