Identification of a Griffiths-like Phase upon Magnetic Dilution and Negative Chemical Pressure at the Fe-Site in PrFeO ₃

The present study identifies a Griffiths-like phase (GP), an exotic magnetic phase transition in PrFeO3, by fine-tuning the complex magnetic exchange interaction through a magnetic dilution process. PrFeO3 diluted at the Fe-sublattice with Ga3+ (30 mol %) and In3+ (20 mol %) has been synthesized, via the solution autocombustion route, and characterized extensively. Along with preservation of the orthorhombic symmetry, we observe local site disorder and strain accompanying the magnetic dilution. An increased bandgap in the Ga- and In-substituted samples, and its indirect nature, were rationalized by the electronic band structure calculations. A magnetic frustration from competing ferromagnetic and antiferromagnetic interactions was evident below 37 K in these samples. Intricate analysis of inverse magnetic susceptibility measurements revealed the emergence of GP, supported by a pronounced ferromagnetic hysteresis at low temperatures. The theoretical calculations indicated that strong Fe(d)-O(p) and Ga/In(s, p)-O(p) hybridizations influenced the overall magnetic properties. Simultaneous magnetic dilution of PrFeO3 with Bi3+ and In3+ led to the suppression of GP.