Electrical studies of orthochromites HoCr0.9TM0.1O3 (TM = Fe and Mn)

In this work, electrical studies made on two orthochromite samples - HoCr0.9TM0.1O3 and HoCr0.9TM0.1O3 as a function of frequency in the range- 100 Hz to 1 MHz and temperature varying from room temperature up to a maximum of 650 K are presented. The two samples have been synthesized employing the solid state diffusion technique. Both the samples crystallize in orthorhombic perovskite structure belonging to space group Pnma. Frequency dependent measurements of real (Z') and imaginary (Z '') parts of impedance are suggestive of samples bearing the negative temperature coefficient of resistance thereby reflecting the typical semiconducting behaviour of both the orthochromite samples. Z '' for higher temperatures (>= 323 K) show a peaking behaviour. With peak maximum shifting towards higher frequency with rising temperature, it owes to the existence of temperature dependent electrical relaxation phenomenon in both the samples. (C) 2020 Elsevier Ltd. All rights reserved.