Maxwell equation for conductivity of dielectrics as the basis of direct relationship of ionic electrical conductivity and mechanical losses in glasses. New problems of physical chemistry of glass

• Published in: Glass physics and chemistry Vol. 38; no. 1; pp. 27 - 40
• Main Author: Nemilov, S. V.
• Format: Journal Article
• Language: English
• Published: Dordrecht SP MAIK Nauka/Interperiodica 01-02-2012; Springer Nature B.V
• Subjects: Ceramics; Characterization and Evaluation of Materials; Chemistry and Materials Science; Composites; Dielectrics; Direct current; Electric potential; Glass; Ionic conductivity; Materials Science; Mathematical analysis; Maxwell equation; Natural Materials; Physical Chemistry; Resistivity; Maxwell electromagnetic theory; relaxation processes; internal friction; conductivity of dielectrics; ionic electrical conductivity
• ISSN: 1087-6596; 1608-313X
• DOI: 10.1134/S1087659612010105

Use of the Maxwell equation for the conductivity of dielectrics and the theory of mechanical losses in glasses caused by ionic shifts has made it possible to calculate directly the temperature of the “ionic” maximum of mechanical losses using data on direct current conductivity. The Maxwell equation was used without changes, in the view accepted in electromagnetic theory. An intuitive physicochemical interpretation of the nature of ionic conductivity measured at constant voltage as a relaxation process was suggested. Verification of the suggestion equation’s validity was performed for one-alkali glasses in silicate, borosilicate, phosphate, borate, and germanate systems. The ratio of calculated and experimental values of the temperature of the “ionic” internal-friction maximum corresponds to 0.995 ± 0.034 and does not depend on the frequency of measurements of internal friction (it changed by four orders) or the parameters characterizing conductivity. These results also confirm the validity of the Maxwell equation for the conductivity of dielectrics. The possibility of describing the direct current ionic conductivity of glasses as a Debye relaxation transition proved in this work is a consequence of the constant voltage condition. The design of a theory for the condition of natural decay of a given potential, when the Kohlrausch relaxation regularity becomes valid, represents a principally important problem of physics and physical chemistry of disordered systems.