研究发现，超冷金属液体在接近玻璃转变时表现出不同的比热容和粘度依赖性，这对其玻璃形成能力有显著影响。通过分子动力学模拟两种模型玻璃形成液体，揭示了这种差异源于它们在温度下降时不同的局部结构有序化。一种加速的短程有序化导致比热容急剧上升和更高的脆弱性，而仅响应液体密度增大的局部构象则使比热容的温度依赖性较弱。
摘要：
Supercooled metallic liquids exhibit very different temperature (T) dependence of the excess specific heat (ΔC_p) and viscosity, profoundly influencing their glass-forming ability. Using two model glass-forming liquids in molecular dynamics simulation, here we demonstrate that their contrasting ΔC_p and relaxation/viscosity behavior has an underlying origin in their different T-dependent local structural ordering. Upon undercooling toward glass transition, a particularly stabilizing type of short-range ordering that accelerates with decreasing T leads to a steeply rising ΔC_p and higher fragility, whereas local motifs that merely respond to the densification of the liquids result in a weak T dependence of ΔC_p.
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