Low-frequency Raman spectra of a glass-forming ionic liquid at low temperature and high pressure.
Low-frequency Raman spectra of a glass-forming ionic liquid at low temperature and high pressure.
复制标题
低温高压下玻璃形成离子液体的低频拉曼光谱。
DOI：
10.1063/1.5094724
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发表时间：
2019
期刊：
影响因子：
--
通讯作者：
M. Ribeiro
中科院分区：
文献类型：
--
作者：
T. Lima;M. Ribeiro
玻璃形成液体的拉曼光谱的低于100 cm-1的频率范围呈现出表征短时（THz）动力学的两个特征：准弹性散射（QES）尾部和玻色子峰（BP）。在这项工作中，我们遵循温度和压力对一个典型的离子液体，1-丁基-1-甲基哌啶鎓双（三氟甲磺酰基）酰亚胺，[Pip 14][[NTf 2]的分子间动力学的影响。[Pip 14][[NTf 2]在大气压下的玻璃化转变温度为Tg = 198 K，并且在室温下的玻璃化转变压力为Pg = 1.1 GPa。当冷却液体或加热玻璃时获得的拉曼光谱在QES和BP强度、IQES和IBP中表现出滞后。IQES、IBP和BP频率ωBP对压力的依赖性在玻璃化转变之前比温度依赖性更陡，这是因为在GPa范围内压力对密度的影响更强。根据其它玻璃形成体的已知结果，讨论了[Pip 14][[NTf 2]的IQES、IBP和ωBP参数的温度和压力行为。
The frequency range below ∼100 cm-1 of the Raman spectrum of a glass-forming liquid exhibits two features that characterize the short-time (THz) dynamics: the quasi-elastic scattering (QES) tail and the boson peak (BP). In this work, we follow temperature and pressure effects on the intermolecular dynamics of a typical ionic liquid, 1-butyl-1-methylpiperidinium bis(trifluoromethanesulfonyl)imide, [Pip14][[NTf2]. The glass transition temperature of [Pip14][[NTf2] at atmospheric pressure is Tg = 198 K, and the pressure of glass transition at room temperature is Pg = 1.1 GPa. Raman spectra obtained while cooling the liquid or heating the glass exhibit hysteresis in QES and BP intensities, IQES and IBP. The dependence of IQES, IBP, and the BP frequency, ωBP, with pressure up to the glass transition is steeper than the temperature dependence due to the stronger pressure effect on density within the GPa range. The temperature and pressure behaviors of the parameters IQES, IBP, and ωBP obtained here for [Pip14][[NTf2] are discussed in light of known results for other glass-formers.
影响因子：
15
作者：
Turton, David A.;Hunger, Johannes;Wynne, Klaas
通讯作者：
Wynne, Klaas
影响因子：
3.4
作者：
D. Turton;Thomas Sonnleitner;A. Ortner;M. Walther;G. Hefter;K. R. Seddon;S. Stana;N. Plechkova;R. Buchner;K. Wynne
通讯作者：
D. Turton;Thomas Sonnleitner;A. Ortner;M. Walther;G. Hefter;K. R. Seddon;S. Stana;N. Plechkova;R. Buchner;K. Wynne