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Materials Research

Print version ISSN 1516-1439

Abstract

SANKARRAJAN, Sundararaman; SAKTHIPANDI, Kathiresan  and  RAJENDRAN, Venkatachalam. Effect of rare earth ions on transition temperature in perovskite materials by on-line ultrasonic studies. Mat. Res. [online]. 2012, vol.15, n.4, pp. 517-521.  Epub June 26, 2012. ISSN 1516-1439.  http://dx.doi.org/10.1590/S1516-14392012005000067.

On-line measurements of ultrasonic longitudinal velocity, shear velocity and longitudinal attenuation were carried out on R1-xSrxMnO3 perovskites (R = La, Pr, Nd and Sm) for different compositions of Sr, at a fundamental frequency of 5 MHz over wide range of temperatures using the through-transmission method. The observed maxima/minima in velocities and attenuation have been discussed with decrease in ionic radii and composition. As a decrease in the ionic radii of rare earth elements leads to a decrease in transition temperature (Tc), the results that are observed show that measurement is one of the best tools to explore the structural/phase transition on-line velocity in perovskite manganese materials as a function of the ionic radii of rare earth elements.

Keywords : perovskite; magnetic materials.

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