Abstract
Dielectric properties of water adsorbed on the SrF2 surface have been investigated under various conditions. A small relaxation was found at 33 kHz, 159 K, and a coverage of 0.74, besides a large relaxation observed at 298 K which had been described in part 1 of this series. This small relaxation is observed only when the physisorbed water molecules are present. Furthermore, the chord length of Cole-Cole plots for this relaxation is found to be a function of the coverage. These findings are interpreted in terms of the Debye-type rotational polarization of the adsorbed water and therefore confirm that the relaxation observed at 298 K is ascribed to the Maxwell-Wagner-type relaxation. An activation energy for the dipole rotation is also calculated from the variation of frequency corresponding to a maximum in the dielectric loss curve with temperature. This result suggests that the rotation of the water molecules condensed two-dimensionally is expected to be moee hindered than that of bulk liquid water, though not so much as in ice. The state of two-dimensionally condensed water on SrF2 is discussed on the basis of the concept of lateral interaction.
Original language | English |
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Pages (from-to) | 2173-2178 |
Number of pages | 6 |
Journal | Langmuir |
Volume | 11 |
Issue number | 6 |
DOIs | |
Publication status | Published - Jun 1 1995 |
Externally published | Yes |
ASJC Scopus subject areas
- Materials Science(all)
- Condensed Matter Physics
- Surfaces and Interfaces
- Spectroscopy
- Electrochemistry