Structural, electrical and magnetic properties studies of perovskites.

      Аннотация: RCr1-xFexO3 (R=Nd/Gd/Er) perovskite nanoparticles were prepared by sol-gel self-combustion technique. All the samples except ErFeO3 sample showed single phase orthorhombic structure. Crystalline size is calculated and is found to be in the order of 50nm. Impedance measurements have carryout at 1Hz-1MHz frequency, RT-500oC temperature range. Impedance of all samples noticed non-Debye and semiconducting behavior. All samples except sample showed the dielectric constant of the dielectric behavior GdFeO3 giant (>103). Conductivity of all samples increased with increasing frequency and temperature. Conductivity decreased with increase in Fe content. All samples except ErFeO3 showed weak ferromagnetic behavior, ErFeO3 exhibited ferromagnetic behavior. Also, MT plots of NdCr1-xFexO3 were carried out under up to 300K at 0.01T, 0. 5T fields. MT curve of x = 0, 0.3 samples at 0.01 exhibited novel magnetic field (diamagnetic like) behavior, with further increase in Fe content reversal magnetism is disappeared. NdCrO3 showed relaxer ferroelectric behavior at near 178oC at 100Hz and 225oC at 100Hz at 1 MHz.

Ключевые слова: Perovskite, giant dielectric, weak ferromagnetic, sol-gel auto-combustion