Correlation between structure and oxygen ion dynamics in Y substituted La2Mo2O9 ionic conductors

We have measured the ac conductivity and dielectric spectra for La2-xYxMo2O9 (0.05 <= x <= 0.20) in wide temperature and frequency ranges. We have obtained the mean square displacement and the spatial extent of nonrandom sub-diffusive regions for oxygen ions by analyzing the ac conductivity and dielectric spectra respectively. The structure of the samples has been studied using X-ray photoelectron spectra, X-ray and electron diffraction. It is observed that the composition dependence of these characteristic lengths is correlated with the distance between oxygen ions obtained from structural studies. (C) 2016 Author(s). All article content, except where otherwise noted, is licensed under a Creative Commons Attribution (CC BY) license (http://creativecommons.org/licenses/by/4.0/).