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The recent discovery of bulk metallic glasses opened the possibility to study their metastable melt far above the glass transition temperature. Alloying 57Fe to the glass ZrTiCuNiBe we succeeded in performing Mossbauer absorption experiments up to 70 K above Tg. While quasi-elastic broadening from structural relaxation was not detected, the Lamb-Mossbauer factor shows an anomalous decrease. From previous neutron spectroscopy, we exclude phonon anharmonicity as a cause. The missing elastic intensity can therefore be ascribed to a fast relaxation process. This is a first indication that the glass transition scenario predicted by mode coupling theory and observed in a number of different systems also applies to metallic alloys.

The Darwin–Hamilton equations, describing one-dimensional transport with scattering and absorption, are expanded into a recursion. The solution involves ballot numbers. The recurrence probability as function of scattering order is given by Catalan numbers. To reproduce this analytical result in a lattice model, a novel relation between Narayana and Catalan numbers is derived.

We have measured depolarized light scattering in liquid benzene over the whole accessible temperature range and over four decades in frequency. Between 40 and 180 GHz we find a susceptibility peak due to structural relaxation. This peak shows stretching and time-temperature scaling as known from $\alpha$ relaxation in glass-forming materials. A simple mode-coupling model provides consistent fits of the entire data set. We conclude that structural relaxation in simple liquids and $\alpha$ relaxation in glass-forming materials are physically the same. A deeper understanding of simple liquids is reached by applying concepts that were originally developed in the context of glass-transition research.