Koç, Nevin SoyluAltıntaş, Sevgi PolatMahamdioua, NabilTerzioğlu, Cabir2021-06-232021-06-2320190925-83881873-4669https://doi.org/10.1016/j.jallcom.2019.05.079https://hdl.handle.net/20.500.12491/9929The size variance (sigma(2)) that indicates random disorder of cations distributed over the A or B-site, has significant influence on the basic quantities on perovskite manganites. In this study, we investigate the effect of A-site variance (sigma(2)(A)) in double layered perovskite manganites. In order to understand how the magneto-electrical properties of layered perovskite type RE2-2xCa1+2xMn2O7 change with sigma(2)(A), we have prepared a series of four samples with optimal doping (x = 0.3) and fixed mean A-cation radius (<r(A)> = 1.3353 angstrom). A-site disorder is varied by use of different rare earth combinations by co-doping of La with Gd, Sm, Nd and Pr. Based on structural analysis by Rietveld profile fitting, all the samples crystallize in Sr3Ti2O7-type tetragonal phase (space group I4/mmm). As sigma(2)(A) increases, paramagnetic (PM) to ferromagnetic (FM) transition temperature shows a linear decrease. However, metal-insulator transition temperature shows a linear correlation with sigma(2). (C) 2019 Elsevier B.V. All rights reserved.eninfo:eu-repo/semantics/closedAccessLayered ManganitesMismatch EffectCrystal StructureArticle10.1016/j.jallcom.2019.05.0797974714762-s2.0-85065776771Q1WOS:000471128700054Q1