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In this paper we present structural, transport, magnetic and magneto-crystalline anisotropy of La1−xSrxMnO3 (х = 0.30, 0.33, 0.36, and 0.40) synthesized using the solid-state reaction method. The X-ray diffraction pattern of the samples is well indexed to the rhombohedral structure with R3̄c space group. Lattice parameters and unit cell volume are found to decrease monotonically upon increasing Sr2+ concentration at La3+ site. X-ray photoelectron spectroscopy confirms the presence of Mn4+ and Mn3+, the ratio of which (Mn4+/Mn3+) increases from 0.44 to 0.64 with increasing Sr2+ concentration. From the ρ(T) and M(T) data analysis, we find that TMI and MS are larger for x = 0.33 composition, suggesting a weakening of the double-exchange interaction due to competing super-exchange interactions in x = 0.30, 0.36 and 0.40 samples. We calculated MCA constant (K1) by fitting the saturation magnetisation data at a higher magnetic field using the law of approach model, M = MS [1-a/H-b/H2]-χH with K12 = (105/8)bMs2 and is in the order of 105 erg/cm3.

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The magnetotransport, magnetic and magnetocaloric properties in the polycrystalline Pr 1−x Sr x MnO 3 (0.20x0.40) have been studied. The X-ray diffraction peaks for the composition x=0.20, 0.33 and 0.40 have been indexed with orthorhombic structure having Pnma space group, whereas x=0.25 composition has been indexed to R-3c space group having rhombohedral symmetry. The substitution of Sr 2+ at Pr 3+ site shows an increase in metal-insulator transition temperature (T MI ) and ferromagnetic ordering temperature (T c ). The composition, x=0.25 shows the higher isothermal magnetic entropy change, DS m | |=2.84 J kg −1 K −1 with RCP=116.33 J kg −1 at ΔH=3 Tesla. The high RCP value (=151.16 J kg −1 ) with DS m | |=2.41 J kg −1 K −1 at ΔH=3 Tesla for the composition, x=0.40, implies that dT fwhm plays a significant role.