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The perovskite manganite sample La0.3Ca0.7Mn1-xWxO3 (x = 0.08, 0.12) was prepared by the solid-state reaction method. The effect of W doping on the Mn site to La0.3Ca0.7MnO3 charge ordering phase and the changing process of mag- netic properties were studied through the measurement of the M-T curve, M-H curves, and ESR curves of the sample. The results showed that when x = 0.08, the charge ordering (CO) phase exists in the system, the transition temperature TCO = 275 K, and the system exhibits PM when T > 275 K. The system transforms from spin-disordering paramagnetism to spin-ordering antiferromagnetism in the charge ordering state with the temperature decreasing from 275 K to 230 K. The long-range antiferromagnetism forms and AFM/CO states coexist between 230 K and 5 K. There is a little ferromagnetic component in the AFM/CO background in a low temperature range. When x = 0.12, the CO phase in the system has almost melted completely. There is a little remnant of the CO phase below 150 K. The system exhibits paramagnetism when T > 150 K and transforms from paramagnetism to ferromagnetism when T < 150 K.
The perovskite manganite sample La0.3Ca0.7Mn1-xWxO3 (x = 0.08, 0.12) was prepared by the solid-state reaction method. The effect of doping on the Mn site to La0.3Ca0.7MnO3 charge ordering phase and the changing process of magnetic properties were studied through the measurement of the MT curve, MH curves, and ESR curves of the sample. The results showed that when x = 0.08, the charge ordering (CO) phase exists in the system, the transition temperature TCO = 275 K, and the system exhibits PM when T> 275 K. The system transforms from spin-disordering paramagnetism to spin-ordering antiferromagnetism in the charge ordering state with the temperature decreasing from 275 K to 230 K. The long-range antiferromagnetism forms and AFM / CO states coexist between 230 K and 5 K. There is a little ferromagnetic component in the AFM / CO background in a low temperature range. When x = 0.12, the CO phase in the system has almost melted completely. There is a little remnant of the CO phase below 15 0 K. The system exhibits paramagnetism when T> 150 K and transforms from paramagnetism to ferromagnetism when T <150 K.