Temperature Behavior of Electric Relaxational Effects due to Ionic Conductivity in Liquid Lactones

• Published in: International journal of thermophysics 2012-05, Vol.33 (5), p.783-794
• Main Authors: Swiergiel, J, Jadzyn, J
• Format: Article
• Language: English
• Subjects: Classical Mechanics; Condensed Matter Physics; Dielectric constant; Dielectrics; Direct current; Industrial Chemistry/Chemical Engineering; Ionic conductivity; Lactones; Liquids; Permittivity; Physical Chemistry; Physics; Physics and Astronomy; Temperature dependence
• ISSN: 0195-928X; 1572-9567
• DOI: 10.1007/s10765-012-1189-x

This paper concerns the studies of temperature and frequency behavior of the complex impedance, electric modulus, and electric conductivity due to an ionic current in liquid γ -butyrolactone (GBL) and γ -valerolactone (GVL). The frequency of the applied electric stimulus (500 Hz to 5 MHz) corresponds to the static dielectric regime of the lactones. The studies were performed in the temperature range of 263 K to 313 K. It was shown that in the static dielectric case, the dc ionic conductivity ( σ DC ) and the static dielectric permittivity determine the relaxational behavior of the impedance ( Z *) and the electric modulus ( M *) of the molecular liquids and both spectra are of the Debye-type characterized by the same conductivity relaxation time ( τ σ ). Both σ DC and τ σ of GBL and GVL fairly well fulfill an Arrhenius temperature dependence with very similar values of the thermal activation energy . The temperature dependence of the static dielectric permittivity and its temperature derivative is analyzed and interpreted in terms of the dipolar aggregation in the studied lactones.