Conductivity dispersion and scaling studies in Na3MY2P3O12 orthophosphate (M2 = Fe2, TiCd, TiZn)

Conductivity dispersion, electric modulus and their scaling are studied for Na3M2P3O12 orthophosphate (M-2 = Fe-2, TiCd, TiZn) glassy and crystallized glassy materials in the frequency range 20 Hz to 1 MHz at different temperatures (T). The power law and the stretched exponential approaches are used to analyze dispersion data. The DC conductivity sigma(DC) of crystallized glass is found to be greater than that of the parent glass. The conductivity scaling is studied with different scaling parameters like hopping frequency omega(p), the Summerfield scaling parameter sigma(DC)T and modified the Summerfield scaling parameter sigma(DC)T/T-x, where alpha shows the temperature dependence. Ngai's correlation is also observed between power-law exponent n and stretched exponent beta. (C) 2004 Elsevier B.V. All rights reserved.