Dielectric modulus analysis of mixed alkali LixRb1-xPO3 glasses

Dielectric data of mixed alkali LixRb1-xPO3 glasses have been analysed in the modulus formalism. The imaginary part of the complex modulus was fitted with a KWW function. The stretching parameter beta is larger in the mixed glasses as compared to the single alkali glasses, which indicates that the mixed alkali glasses behave as single alkali glasses of effectively lower concentrations. The finding is consistent with the random ion distribution model, which assumes that the two kinds of alkali ions are moving in distinctly different conduction pathways