Magnetic properties, crystal and electronic structure of GdNi5−xCux series
Magnetic properties, crystal and electronic structure of GdNi5−xCux series
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GdNi5−xCux系列的磁性能、晶体和电子结构
DOI：
10.1016/j.jallcom.2010.09.195
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发表时间：
2011
影响因子：
6.2
通讯作者：
B. Andrzejewski
中科院分区：
文献类型：
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作者：
A. Bajorek;G. Chełkowska;B. Andrzejewski
研究了 Ni/Cu 取代对多晶 GdNi5−xCux 系列磁性能、晶体和电子结构的影响。所有化合物均以六方 CaCu5 型晶体结构（空间群 P6/mmm）结晶。根据 χAC(T) 磁化率以及低于室温的磁化强度 M(T) 估算的磁相变 (Tmag) 的温度依赖性表明 x=1.0 铜浓度的最大值。在顺磁范围（高于 300K），磁化率遵循居里-魏斯型依赖性。游离Gd3+的有效磁矩高于理论值。根据 X 射线光电子能谱 (XPS) 数据，分析了价带和核心能级光谱。 Ni2p 核心能级光谱中卫星强度的降低揭示了 GdNi5−xCux 系统中 Ni3d 能带通过 Gd 传导电子的电荷转移而填充。所得结果表明，费米能级的价带主要由杂化的 Ni3d 和 Gd5d 态主导，而 Cu3d 态相当局域于费米能级以下约 3eV 处。已经发现磁性和电子结构之间有很好的关系。
The effect of Ni/Cu substitution on the magnetic properties, crystal and electronic structure of the polycrystalline GdNi5−xCuxseries has been studied. All compounds crystallize in the hexagonal CaCu5 type of crystal structure (space group P6/mmm). The temperature dependence of magnetic phase transition (Tmag) estimated from χAC(T) susceptibility as well as magnetization M(T) below room temperature indicates the maximum for x=1.0 copper concentration. In the paramagnetic range (above 300K) the magnetic susceptibilities follow a Curie–Weiss-type dependence. The effective magnetic moments are higher than theoretical value for free Gd3+. From X-ray photoelectron spectroscopy (XPS) data the valence band as well as the core level spectra have been analyzed. The filling of Ni3d band in the GdNi5−xCuxsystem by charge transfer of Gd conduction electrons is revealed by a reduction of the satellite intensities in the Ni2p core level spectrum. The obtained results exhibit that the valence bands at the Fermi level are dominated by hybridized Ni3d and Gd5d states, when Cu3d states are rather localized about 3eV below the Fermi level. Quite good relation between the magnetic properties and electronic structure has been found.