Evolution of Temperature-Dependent Electrical and Magnetic Behavior in a Series of Antimonate Triple Perovskite Sr ₃ CoSb _{2– <i>x</i>} Ti _<i>x</i> O ₉

Motivated by several claims of perovskites that incorporate Sr metal at the A site, they frequently exhibit distinctive orthorhombic structures, which feature multiple potential sites that the B cations are able to acquire. It has been well-established that Sr₃Sb_2-<i>x</i>Ti_<i>x</i>CoO₉ (<i>x</i> = 0.0, 0.1, and 0.5) exhibits a single-phase orthorhombic structure (<i>Immm</i> space group). This outlines a chance to explore the onset of electronic and magnetic characteristics in accordance with the doping levels. Temperature-dependent magnetic susceptibility measurements exhibit the divergence between ZFC and FC curves at low temperatures, indicating magnetic irreversibility and the onset of spin frustration. Curie-Weiss analysis indicates elevated effective magnetic moments and progressively negative Weiss temperatures with doping, aligning with developed antiferromagnetic interactions and the onset of magnetic frustration. The <i>M</i>-<i>H</i> and Arrott plots validate the presence of mild ferromagnetic characteristics in doped samples, presumably resulting from Co²⁺/Co³⁺ valence variations caused by Ti⁴⁺ substitution. Dielectric measurements reveal significant frequency dispersion and relaxor-type behavior, with ac conductivity conforming to the associated CBH and NSPT models for the respective doping series. The fluctuation of <i>s</i> parameters with temperature further corroborates the influence of thermally activated charge dynamics. These findings emphasize the dual function of Ti⁴⁺ doping in influencing spin correlations and dielectric relaxation, indicating potential multifunctional applications in magneto-dielectric materials.