Analysis of relationship between magnetic property and crystal structure of La1−xSrxCrO3 (, 0.15)

Dependence of dc magnetization, M , of La1−xSrxCrO3 ( x = 0.13 , 0.15) polycrystalline specimens on external magnetic field, H , was measured at various temperatures. At higher temperatures above 274 K and 265 K for the specimens with x = 0.13 and 0.15, respectively, almost linear relationships were observed, indicating paramagnetic property. At the lower temperatures, hystereses, indicating canted antiferromagnetic property, were observed in M – H curves. The temperatures where the magnetic phase transition was observed showed agreement with those where base line shift was observed in differential scanning calorimetry (DSC) measurement. In the M – H curves of La1−xSrxCrO3 ( x = 0.13 , 0.15), saturation magnetization, M s , was not observed at external magnetic fields as high as 70 kOe. At 226 K and 189 K for the specimens with x = 0.13 and 0.15, respectively, structural phase transition from orthorhombic- to rhombohedral-distorted perovskite was observed in DSC curves. At the temperature, abrupt decreases of residual magnetization, M r , and variation of temperature dependence of coercive force, H c , were detected. We regard that the abrupt decrease of M r and the variation of temperature dependence of H c at the structural phase transition temperature can be ascribed to discontinuous variation of Cr–O–Cr angles.