Phase Transition of La0.62Sr0.38MnO3 Perovskite Manganites

Sakthipandi K,Selvam M

doi:10.34256/famr1915

Abstract

Bulk and nano La0.62Sr0.38MnO3 perovskite manganite samples were prepared using solid state and sonochemical reaction respectively. The ultrasonic velocities measurement was made on prepared samples using ultrasonic through transmission method, at a fundamental frequency of 5 MHz over wide range of temperatures. The temperature dependence of the ultrasonic parameters shows an interesting anomaly in bulk and nano perovskite samples. The observed dramatic softening and hardening in sound velocities are related to phase transitions. Further, a decrease in grain size in the nanostructured sample leads to a shift in the ferromagnetic transition temperature (TC) from 375 to 370 K.

Highlights

The peaks observed at materials, La0.68Sr0.32MnO3 (LSMO) perovskite, 27.616o and 48.365o correspond to tetragonal phase and the existence of highest value of Curie temperature (TC) and other peaks correspond to rhombohedra phase (JCPDS file very low carrier density with a high spin polarisation of no.: 89-4461 and 51-0118)
The nanostructured the hexagonal structure (JCPDS file no.: 51-0409) is materials are used to widen the opportunities to improve the observed in the nano LSMO perovskite
Properties of the doped perovskite materials depend on (i) bulk LSMO perovskite samples have sphere like morphology, doping concentration (x) [5], (ii) ionic size of A site divalent whereas nano LSMO perovskite samples have honeycomb cation [6], (iii) the variation of doped ions and potential structure consisting of agglomerated nanoparticles with fluctuations between R3+ and A2+ [7] and (iv) phase particle sizes ranging from 30 to 50 nm

Summary

Introduction

In the past few years, perovskite manganites R1- and on-line ultrasonic measurements [4, 9]. Result and Discussion divalent alkaline earth ions) were attracted for potential The XRD patterns of bulk and nano LSMO

Results

Conclusion