The Dielectric Relaxation of Water on Addition of Ethylene Carbonate and some Related Substances

1989 ◽  
Vol 44 (1) ◽  
pp. 56-58
Author(s):  
M. Stockhausen ◽  
A. Lux
Keyword(s):  
Dielectric Properties ◽  
Aqueous Solutions ◽  
Dielectric Relaxation ◽  
Propylene Carbonate ◽  
Ethylene Carbonate ◽  
Related Substances ◽  
Hydration Model

Abstract The dynamic dielectric properties of diluted aqueous solutions of propylene carbonate, ethylene carbonate (EC). 4-butyrolactone and cyclohexanone (CH) have been measured at 20 °C. On assuming normal solute relaxation, the water relaxation can be described by two superimposed Debye type contributions, which may be interpreted in terms of a hydration model. Qualitatively, the influence on the water relaxation increases from EC to CH.

Dielectric relaxation of lithium and sodium perchlorates in 1,2-dimethoxyethane and propylene carbonate

1981 ◽  
Vol 59 (7) ◽  
pp. 1051-1060 ◽  
Author(s):  
Hubert Cachet ◽  
Mohamed Fekir ◽  
Jean-Claude Lestrade
Keyword(s):  
Dielectric Properties ◽  
Ethyl Acetate ◽  
Dielectric Relaxation ◽  
Propylene Carbonate ◽  
Complex Permittivity ◽  
Ion Pairs ◽  
Conductivity Measurements ◽  
Frequency Range ◽  
Dielectric Data

The complex permittivity of LiClO4 and NaClO4 solutions in 1,2-dimethoxyethane (DME) has been measured in the frequency range 0.140–123.2 GHz. The data have been analysed according to a model for the reorientation of ion pairs given in a previous paper. The dielectric data are supplemented by conductivity measurements in a broad concentration range (10−4–1 mol/L) which evidence the large extent of salt association. The main result is that the solvation of Li+ and Na+ by DME cannot be described as simply as in the case of other solvents, such as tetrahydrofuran or ethyl acetate, as far as the dielectric properties are concerned: while the assumption of rigidly bound solvating molecules was acceptable for the latter solvents, some freedom in the reorientation of these molecules has to be taken into account for the case of DME. LiClO4 solutions in propylene carbonate (PC) + benzene and PC + DME mixtures have also been studied. The data, for the latter, can be qualitatively interpreted under the assumption that PC molecules take the place of DME molecules in the solvation sheath, even at low PC concentration.

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