Berthier Ludovic, Tarjus Gilles
Laboratoire des Colloïdes, Verres et Nanomatériaux, Université Montpellier II and CNRS, 34095 Montpellier, France.
Phys Rev Lett. 2009 Oct 23;103(17):170601. doi: 10.1103/PhysRevLett.103.170601. Epub 2009 Oct 22.
We study the role of the attractive intermolecular forces in the viscous regime of a simple glass-forming liquid by using computer simulations. To this end, we compare the structure and the dynamics of a standard Lennard-Jones glass-forming liquid model with and without the attractive tail of the interaction potentials. The viscous slowing down of the two systems is found to be quantitatively and qualitatively different over a broad density range, whereas the static pair correlations remain close. The common assumption that the behavior of dense nonassociated liquids is determined by the short-ranged repulsive part of the intermolecular potentials dramatically breaks down for the relaxation in the viscous liquid regime.
我们通过计算机模拟研究了吸引性分子间力在简单玻璃形成液体粘性区域中的作用。为此，我们比较了具有和不具有相互作用势吸引尾的标准 Lennard-Jones 玻璃形成液体模型的结构和动力学。发现在很宽的密度范围内，这两个系统的粘性减慢在定量和定性上都有所不同，而静态对关联仍然相近。关于稠密非缔合液体的行为由分子间势的短程排斥部分决定这一普遍假设，在粘性液体区域的弛豫过程中被显著打破。
