Correlating structure, magnetism, and electrical transport in sol-gel processed Nd0.55Ca0.45MnO3 manganite

This study explores the synthesis and comprehensive analysis of nanocrystalline Nd 0.55 Ca 0.45 MnO 3 (NCMO-11) to elucidate the influence of nano-size on its multifunctional properties. The sol-gel method synthesized NCMO-11, which exhibited a well-defined orthorhombic perovskite structure with notable Jahn-Teller distortions. Morphological studies revealed agglomerated granules with an average particle size of ∼81 nm. Magnetic measurements highlighted a complex interplay of antiferromagnetic and ferromagnetic phases, characterized by a charge-ordering transition at T CO ∼233 K and ferromagnetic ordering at T CON ∼149 K. Transport studies indicated an insulator-metal transition (IMT) around T IMT ∼98 K during cooling, accompanied by thermal hysteresis, suggesting strong phase competition. Dielectric studies revealed exceptionally high dielectric constants at low frequencies, attributable to interfacial polarization, while optical analyses showed a wide bandgap of 4.07 eV, emphasizing the material's potential in UV-responsive technologies. These findings underscore the critical impact of nanoscale effects on the structural, magnetic, transport, and optical behavior of NCMO-11, establishing its suitability for advanced applications in electronics, magnetics, and optoelectronics. • Nd₀.₅₅Ca₀.₄₅MnO₃ nanocrystalline sample was synthesized using the sol-gel method. • A hysteresis amid FCW and FCC cycles reflected competing AFM and FM interactions. • The material revealed an IMT∼ 98 K during cooling, accompanied by thermal hysteresis. • A refractive index of ∼2.003 underscores its potential for optoelectronic purpose. • The ρ-T data supported phase competition between AFM insulating and FM metallic states.