Second-Order Magnetic Transition in La0.67Ca0.33-xSr x MnO3 (x = 0.05, 0.06, 0.07, 0.08)

The magnetocaloric properties and the mag- netic phase transition of the rare earth manganites La0.67 Ca0.33-x Srx MnO3 (x = 0.05, 0.06, 0.07, 0.08) have been studied. Three methods were used to determine the order of the magnetic transition: isothermal magnetization curves; magnetization as a function of the temperature; and the phenomenological, universal curve. And it was found to be a second-order transition.