论文标题
单域mg $ _ {1-x} $ ni $ _x $ fe $ _2 $ o $ $ _4 $（$ 0 \ le x \ le x \ le 1.0 $）纳米晶体的结构和软磁性
Structure and soft magnetic properties of single-domain Mg$_{1-x}$Ni$_x$Fe$_2$O$_4$ ($0 \le x \le 1.0$) nanocrystals
论文作者
论文摘要
ni $^{2+} $替换对结构的影响（晶格参数，阳离子分布，平均阳离子半径，阳离子阳离子/阴离子键和角度和角度）以及mg $ _ {1-x} $ ni $ _x $ _x $ _x $ fe $ _2 $ _2 $ $ _4 $ $ _4 $ $ 0 \ le x的软磁性X射线衍射，可通过Rietveld细化，透射电子显微镜，Mossbauer光谱和磁化测量值进行X射线衍射。在MGFE $ _2 $ o $ _4 $纳米颗粒中发现了大部分逆尖晶石结构，并且通过Ni-Subsubtitution直至Nife $ _2 $ o $ $ _4 $的完整反转，进一步增加了反转因子。具有较小粒径（20-30 nm）的合成铁氧体表现出具有临界域大小约30-40 nm的单域行为的软磁性能。观察到的单调增加的磁化增加和通过Ni-bibstitution在5 K处的强大降低导致X = 0.5的各向异性常数KU（2.8 kJ/m3）的最低。我们讨论了通过Ni-substitution与随后的两个Sublattices位点之间的阳离子重新分配以及离子间距离的相应结构变化的相关性。
The effects of Ni$^{2+}$ substitution on the structure (lattice parameters, cations distribution, average cations radii, cation-cation/anion bond lengths and angles) and the soft magnetic properties of Mg$_{1-x}$Ni$_x$Fe$_2$O$_4$ ($0 \le x \le 1.0$) nanocrystals have been studied by x-ray diffraction with Rietveld refinement, transmittance electron microscopy, Mossbauer spectroscopy and magnetization measurements. The mostly inverse spinel structure was found in MgFe$_2$O$_4$ nanoparticles and the inversion factor is further increased by Ni-substitution up to a complete inversion in NiFe$_2$O$_4$. The synthesized ferrites with a small particle size (20 - 30 nm) exhibit soft magnetic properties of a single-domain behavior with critical domain size about 30 - 40 nm. An observed monotonic increase in magnetization and drastic decrease in coercivity at 5 K by Ni-substitution result in a lowest anisotropy constant Ku (2.8 kJ/m3) for x = 0.5. We discuss the evolution of magnetic properties by Ni-substitution in a correlation with a subsequent cations-redistribution between sites of the two sublattices and corresponding structural changes in the inter-ionic distances.
