A possible structural signature of the onset of cooperativity in metallic liquids

It is widely, although not universally, believed that there must be a connection between liquid dynamics and the structure. Previous supporting studies, for example, have demonstrated a link between the structural evolution in the liquid and kinetic fragility. Here, new results are presented that strengthen the evidence for a connection. By combining the results from high-energy synchrotron X-ray scattering studies of containerlessly processed supercooled liquids with viscosity measurements, an accelerated rate of structural ordering beyond the nearest neighbors in the liquid is demonstrated to correlate with the temperature at which the viscosity transitions from Arrhenius to super-Arrhenius behavior. This is the first confirmation of predictions from several recent molecular dynamics studies.