采用溶胶一凝胶法在不同烧结温度下制备了双钙钛矿结构化合物Sr_2FeMoO_6,研究了烧结温度对样品B位阳离子的有序度和饱和磁化强度的影响,测量了样品电阻率随温度变化的曲线.X射线衍射实验表明,所有样品中无杂相产生,晶体结构均为四方结构.样品的有序度随烧结温度的升高而增大,而有序度越高的样品饱和磁化强度也越大;样品在30000Oe磁场下的导电行为呈现出由半导体导电行为(低温区T≈10～80K)向金属导电行为(高温区了T≈80～300K)的转变.
The double-perovskite Sr_2FeMoO_6 compounds have been prepared under different sintering temperature by sol-gel method. The influence of sintering temperature on B site cationic ordering degree and saturation magnetization is investigated. At the same time, the curve of resistivity is measured. X-ray powder diffraction profiles indicates that all the samples are pure phase and crystal structure is tetragonal. The samples' ordering degree increases with the sintering temperature rising. The higher ordering degree is, the higher saturation magnetization is. The sample show a conversion from semi-conductor conduction behavior to metal conductor behavior in the case that the magnetic field is 30000Oe.
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