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arXiv · 1106.5614

Hydrogen-bond equilibria and life times in a supercooled monohydroxy alcohol

C. Gainaru·S. Kastner·F. Mayr·P. Lunkenheimer·S. Schildmann·H. J. Weber·W. Hiller·A. Loidl·R. Böhmer
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Abstract

Dielectric loss spectra covering 13 decades in frequency were collected for 2-ethyl-1-hexanol, a monohydroxy alcohol that exhibits a prominent Debye-like relaxation, typical for several classes of hydrogen-bonded liquids. The thermal variation of the dielectric absorption amplitude agrees well with that of the hydrogen-bond equilibrium population, experimentally mapped out using near infrared (NIR) and nuclear magnetic resonance (NMR) measurements. Despite this agreement, temperature-jump NIR spectroscopy reveals that the hydrogen-bond switching rate does not define the frequency position of the prominent absorption peak. This contrasts with widespread notions and models based thereon, but is consistent with a recent approach.

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C. Gainaru, S. Kastner, F. Mayr, P. Lunkenheimer, S. Schildmann, H. J. Weber, W. Hiller, A. Loidl, R. Böhmer. 2011-06-29. Hydrogen-bond equilibria and life times in a supercooled monohydroxy alcohol. https://doi.org/10.1103/physrevlett.107.118304

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