Molecular Nano-Optics and Spins group, Leiden Institute of Physics, Leiden University, Postbus 9504, 2300 RA, Leiden, The Netherlands.
J Chem Phys. 2012 Jan 28;136(4):041102. doi: 10.1063/1.3681292.
Heterogeneity and solid-like structures found near the glass transition provide a key to a better understanding of supercooled liquids and of the glass transition. However, the formation of solid-like structures and its effect on spatial heterogeneity in supercooled liquids is neither well documented nor well understood. In this work, we reveal the crystalline nature of the solid-like structures in supercooled glycerol by means of neutron scattering. The results indicate that inhomogeneous nucleation happens at temperatures near T(g). Nevertheless, the thermal history of the sample is essential for crystallization. This implies such structures in supercooled liquids strongly depend on thermal history. Our work suggests that different thermal histories may lead to different structures and therefore to different length and time scales of heterogeneity near the glass transition.
在玻璃化转变附近发现的非均匀性和类固体结构为更好地理解过冷液体和玻璃化转变提供了关键线索。然而，类固体结构的形成及其对过冷液体空间非均匀性的影响既没有得到很好的记录，也没有得到很好的理解。在这项工作中，我们通过中子散射揭示了过冷甘油中类固体结构的结晶性质。结果表明，在接近 Tg 的温度下发生了不均匀成核。然而，样品的热历史对于结晶是至关重要的。这意味着过冷液体中的这些结构强烈依赖于热历史。我们的工作表明，不同的热历史可能导致不同的结构，从而导致玻璃化转变附近的异质性具有不同的长度和时间尺度。
