Logo image
Dielectric relaxation of aqueous Na2CO3 solutions
Journal article   Peer reviewed

Dielectric relaxation of aqueous Na2CO3 solutions

S.G. Capewell, R. Buchner, G. Hefter and P.M. May
Physical Chemistry Chemical Physics, Vol.1(8), pp.1933-1937
1999
url
Link to Published Version *Subscription may be requiredView

Abstract

The complex dielectric permittivity of aqueous sodium carbonate solutions (0.05 ≤ c/mol L-1 ≤ 2.5) has been determined in the frequency range 0.2 ≤ v/GHz ≤ 20 at 25.0 °C with a commercial dielectric measurement system based on a vector network analyser. A superposition of three Debye relaxation processes was necessary to fit the complex permittivity spectra. The slow and intermediate dispersion steps are assigned to double solvent separated (2SIP) and solvent-shared (SSIP) NaCO3-(aq) ion-pairs respectively. The absence of contact ion-pairs was confirmed by Raman spectroscopy. The fast process is assigned to the collective relaxation of the solvent. Equilibrium constants for the formation of NaCO3-(aq) were determined from the ion-pair dispersion amplitudes. The effect of Na2CO3 concentration on the water dispersion amplitude allowed effective solvation numbers to be deduced.

Details

Metrics

4 File views/ downloads
73 Record Views
Logo image