Abstract:
We have synthesized SmCr0.85Mn0.15O3 (SCMO) chromites through the ceramic route. The
compound crystallized into a distorted orthorhombic structure with the Pnma space group, which
was confirmed from the Rietveld refinement of x-ray powder diffraction patterns. Neel temperature,
noticed at 168K from the temperature variation of magnetisation, smaller than that reported for
SmCrO3, indicated the influence of Mn3þ substitution on decreasing the antiferromagnetic ordering.
A phenomenon of magnetization reversal was observed in the SCMO compound. At low magnetic
fields, i.e., 500 Oe, a single compensation temperature (defined as the temperature where
magnetization became zero) around 106K was observed in the field cooled magnetization curve.
However, with the application of higher magnetic fields, i.e., under an applied field of 1000 Oe, a
second compensation temperature was noticed around 8K. With a further increase in the magnetic
field, the magnetization remained positive in both field cooled and zero field cooled protocols. A
normal magnetocaloric effect was observed through an indirect method of field dependence of
magnetisation measured in the temperature range of 2–152 K. The magnetic entropy change ( DS)
of 11.36 J kg 1 K 1 along with the relative cooling power (RCP) of 175.89 J kg 1 was obtained
in the temperature range of 10–20K for an applied field of 90 kOe, and their values at 50 kOe
applied field were, respectively, almost twenty and forty times larger in magnitude in comparison
to those for the SmCrO3 compound. The relatively large values of DS and RCP make the studied
compound a potential candidate for magnetic refrigeration applications at low temperatures.
Published by AIP Publishing
