Voylov D N, Griffin P J, Mercado B, Keum J K, Nakanishi M, Novikov V N, Sokolov A P
Department of Chemistry, University of Tennessee, Knoxville, Tennessee 37996, USA.
Department of Materials Science and Engineering, University of Pennsylvania, Philadelphia, Pennsylvania 19104-6272, USA.
Phys Rev E. 2016 Dec;94(6-1):060603. doi: 10.1103/PhysRevE.94.060603. Epub 2016 Dec 29.
Detailed analysis of the static structure factor S(Q) in several glass-forming liquids reveals that the temperature variations of the width of the main diffraction peak ΔQ(T) correlate with the fragility of these liquids. This observation suggests a direct connection between rather subtle structural changes and sharp slowing down of structural relaxation in glass-forming liquids. We show that this observation can be rationalized using the Adam-Gibbs approach, through a connection between temperature variations of structural correlation length, l_{c}∼2π/ΔQ, and the size of cooperatively rearranging regions.
对几种玻璃形成液体中静态结构因子S(Q)的详细分析表明,主衍射峰宽度ΔQ(T)的温度变化与这些液体的脆性相关。这一观察结果表明,在玻璃形成液体中,相当细微的结构变化与结构弛豫的急剧减慢之间存在直接联系。我们表明,通过结构关联长度l_c∼2π/ΔQ的温度变化与协同重排区域大小之间的联系,可以用亚当-吉布斯方法对这一观察结果进行合理的解释。