A nuclear magnetic resonance study of higher-order correlation functions in supercooled ortho-terphenyl
A nuclear magnetic resonance study of higher-order correlation functions in supercooled ortho-terphenyl
复制标题
过冷邻三联苯高阶相关函数的核磁共振研究
DOI：
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发表时间：
1998
期刊：
影响因子：
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通讯作者：
H. Sillescu
中科院分区：
文献类型：
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作者：
R. Böhmer;G. Diezemann;G. Hinze;H. Sillescu
使用氘NMR技术的两个，有效的三，和各种四时间的相关函数记录过冷邻三联苯在10-15 K以上的量热玻璃化转变，以表征其主要响应的异质性。实验结果可以成功地描述在各种能源景观模型，以及通过连续时间随机游走模拟。这些理论上的考虑为动态非均匀性的定义提供了一个合适的基础。我们讨论的权力，但也有一些局限性，目前的多维NMR技术时，适用于无定形材料。
Using deuteron NMR techniques two-, effective three-, and various four-time correlation functions were recorded for supercooled ortho-terphenyl at 10–15 K above the calorimetric glass transition in order to characterize the heterogeneous nature of its primary response. The experimental results could successfully be described within various energy landscape models as well as via continuous time random walk simulations. These theoretical considerations provide a suitable basis for a definition of the term dynamic heterogeneity. We discuss the power but also some limitations of the present multidimensional NMR techniques when applied to amorphous materials.