Huth Heiko, Wang Li-Min, Schick Christoph, Richert Ranko
Institute of Physics, University of Rostock, Universitätsplatz 3, 18051 Rostock, Germany.
J Chem Phys. 2007 Mar 14;126(10):104503. doi: 10.1063/1.2539105.
Dielectric relaxation and dynamic heat capacity measurements are compared for 2-ethyl-1-hexanol near its glass transition temperature Tg in order to further clarify the origin of the prominent Debye-type loss peak observed in many monohydroxy alcohols and other hydrogen-bonding liquids. While the dielectric spectrum epsilon" displays two distinct polarization processes that are separated by a factor of 2000 in terms of the peak frequency, the heat capacity cp" shows only a single peak. The dielectric process with lower amplitude and higher peak frequency coincides with the calorimetric signal, whereas the large dielectric Debye signal is not associated with calorimetric modes. The authors conclude that the Debye process corresponds to a transition among states which differ in energy only in the case of an external electric field.
对2-乙基-1-己醇在其玻璃化转变温度Tg附近进行介电弛豫和动态热容测量，以进一步阐明在许多单羟基醇和其他氢键液体中观察到的显著德拜型损耗峰的起源。虽然介电谱ε"显示出两个不同的极化过程，在峰值频率方面相差2000倍，但热容cp"仅显示一个峰。幅度较小且峰值频率较高的介电过程与量热信号一致，而大的介电德拜信号与量热模式无关。作者得出结论，德拜过程对应于仅在外部电场情况下能量不同的状态之间的转变。
