Liquid 1-propanol studied by neutron scattering, near-infrared, and dielectric spectroscopy
Liquid 1-propanol studied by neutron scattering, near-infrared, and dielectric spectroscopy
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DOI：
10.1063/1.4868556
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发表时间：
2014-03-28
影响因子：
4.4
通讯作者：
Boehmer, R.
中科院分区：
文献类型：
--
作者：
Sillren, P.;Matic, A.;Boehmer, R.
结构.利用准弹性中子散射，结合飞行时间和中子自旋回波技术，研究了液态1-丙醇的结构和动力学之间的联系，重点研究了结构因子主峰和前峰对应的长度尺度上的动力学.在主峰处，探测结构弛豫时间。这些对应以及从文献数据计算的机械弛豫时间。在前峰处，对应于与氢键结构相关的长度尺度，弛豫时间几乎长一个数量级。根据前人的工作[ C.盖纳鲁河迈耶，S。Schildmann角Lederle，W. Hiller，E. Rssler和R. Bhmer，Phys. Rev. Lett. 105，258303（2010）]该时间尺度差异与H键合簇的平均尺寸有关。根据正丙醇的宽带介电常数数据，讨论了中子散射弛豫时间与介电谱弛豫时间之间的关系。此外，在1-丙醇的介电弛豫强度以及近红外吸收揭示了环境温度以下的异常行为。在多元醇丙二醇和甘油中没有发现相应的特征。(c)2014 AIP Publishing LLC.
structures. The connection between structure and dynamics is studied for liquid 1-propanol using quasi-elastic neutron scattering, combining time-of-flight and neutron spin-echo techniques, with a focus on the dynamics at length scales corresponding to the main peak and the pre-peak of the structure factor. At the main peak, the structural relaxation times are probed. These correspond well to mechanical relaxation times calculated from literature data. At the pre-peak, corresponding to length scales related to H-bonded structures, the relaxation times are almost an order of magnitude longer. According to previous work [ C. Gainaru, R. Meier, S. Schildmann, C. Lederle, W. Hiller, E. Rssler, and R. Bhmer, Phys. Rev. Lett. 105, 258303 ( 2010)] this time scale difference is connected to the average size of H-bonded clusters. The relation between the relaxation times from neutron scattering and those determined from dielectric spectroscopy is discussed on the basis of broad-band permittivity data of 1- propanol. Moreover, in 1-propanol the dielectric relaxation strength as well as the near-infrared absorbance reveal anomalous behavior below ambient temperature. A corresponding feature could not be found in the polyalcohols propylene glycol and glycerol. (c) 2014 AIP Publishing LLC.