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Updated: Feb 26, 2026
Probing the Structure and Dynamics of Interfacial Water with Scanning Tunneling Microscopy and Spectroscopy
Published on: May 27, 2018
Dielectric and structural relaxation in water and some monohydric alcohols
1Drittes Physikalisches Institut, Georg-August-Universität Göttingen, Friedrich-Hund-Platz 1, 37077 Göttingen, Germany.
Abstract:
Relaxation times of the principal (Debye-type) relaxation terms in the dielectric spectra of water and normal alcohols have been evaluated in order to eliminate the effect of multi-molecular cross-correlations and to thus yield reorientation times of the molecular electric dipole moments. The reorientation times have been compared to relaxation times from ultraviolet and X-ray Brillouin spectra as well as from broadband ultrasonic spectra, which are considered as the structure relaxation times characterizing the density fluctuations of the liquid hydrogen bond networks. With some alcohols, shear impedance spectra indicate the network fluctuations to be tightly associated with shear viscosity relaxation. Within the limits of uncertainty, the molecular dipole moment reorientation times and the structure relaxation times feature close correlations. This finding suggests a coupling between translational and orientational molecular motions, and it is discussed in the light of the wait-and-switch model of dielectric relaxation.
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