Microscopic dynamics in liquid GeO2 - art. no. 212202

We investigate liquid GeO2 with inelastic neutron scattering at temperature s up to two times the glass transition temperature T-g. Structural relaxati on is still too slow to be resolved by the instrumental resolution. The ine lastic spectra reveal a pronounced peak at 3 meV. The position of the peak maximum shows no dispersion in wave number q. Over the full-energy range sp ectra scale with the Bose occupation as expected for harmonic vibrations. F or energies below similar or equal to 2 meV the dynamic susceptibility show s a linear energy dependence that can be attributed to harmonic acousticlik e excitations. There is no indication for a fast beta -relaxation process a s predicted by mode coupling theory.