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对钙钛矿结构锰酸盐巨磁电阻材料进行了阴离子掺杂的研究.X 射线衍射结果表明,La2/3Ca1/3M(O1- xFx)3化合物的空间群为Pbnm ,Z=4,F- 离子占据8d 位置, 随着CaF2 掺入量的增加,晶格常数和晶胞体积呈递减趋势.CaF2 的掺入使居里温度Tc 升高.分别在0 磁场和H= 3977kA/m 的外加磁场下进行阻温曲线的测量,各试样巨磁电阻比率ΔR/R0的峰值均在67% 以上,掺3 % (物质的量百分数)CaF2 时ΔR/R0 最大, 峰值达到74% .
Anion doping of perovskite manganites giant magnetoresistance material was studied. X-ray diffraction results show that the space group of La2 / 3Ca1 / 3M (O1-xFx) 3 compounds is Pbnm, Z = 4 and F- ions occupy the 8d position. With the increase of CaF2 incorporation, the lattice constant and unit cell Volume showed a decreasing trend. The incorporation of CaF2 increases the Curie temperature Tc. The temperature-dependent curves were measured under the applied magnetic field of 0 and H = 3977kA / m respectively. The peak values of the giant magnetoresistance (ER) ratio were all over 67% and 3% (mass fraction) of CaF2 ΔR / R0 maximum, the peak reached 74%.