Yamaguchi Tsuyoshi, Saito Makina, Yoshida Koji, Yamaguchi Toshio, Yoda Yoshitaka, Seto Makoto
Graduate School of Engineering, Nagoya University , Furo-cho B2-3 (611), Chikusa, Nagoya, Aichi 464-8603, Japan.
Research Reactor Institute, Kyoto University , Kumatori, Osaka 590-0494, Japan.
J Phys Chem Lett. 2018 Jan 18;9(2):298-301. doi: 10.1021/acs.jpclett.7b02907. Epub 2018 Jan 4.
This work studied the slow dynamics of liquids with mesoscopic structure and its relation to shear viscosity. Quasielastic scattering measurements were made on a liquid higher alcohol, 3,7-dimethyl-1-octanol, using γ-ray time-domain interferometry at a synchrotron radiation facility, SPring-8. The quasielastic scattering spectra were measured to determine the structural relaxation at two wavenumbers of the prepeak and the main peak of the static structure factor. It was found that relaxation at the prepeak is more than 10 times slower than that at the main peak. Compared with the viscoelastic spectrum, which exhibits bimodal relaxation, the relaxations at the prepeak and the main peak were shown to correspond to the slower and faster modes of the viscoelastic relaxation, respectively. This indicates that the dynamics of the mesoscopic structure represented as the prepeak contributes to the shear viscosity through the slowest mode of the viscoelastic relaxation.
本研究探讨了具有介观结构的液体的慢动力学及其与剪切粘度的关系。在同步辐射设施SPring-8上，使用γ射线时域干涉术对液态高级醇3,7-二甲基-1-辛醇进行了准弹性散射测量。测量准弹性散射光谱以确定静态结构因子的前峰和主峰两个波数处的结构弛豫。结果发现，前峰处的弛豫比主峰处的弛豫慢10倍以上。与呈现双峰弛豫的粘弹性光谱相比，前峰和主峰处的弛豫分别对应于粘弹性弛豫的较慢和较快模式。这表明，以前峰表示的介观结构动力学通过粘弹性弛豫的最慢模式对剪切粘度有贡献。
