We report our analysis of thermopower of (, 0.04, 0.08, and 0.1) compounds within a percolative framework and correlate the results with the existence of a Griffiths phase. The Griffiths temperature, at which ferromagnetic metallic clusters nucleate above , is evaluated. We further show that the Griffiths phase extends over a higher temperature range above with increase in the variance of ionic radii of the site.
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