DIRECT DETERMINATION OF PRASEODYMIUM VALENCE IN PR2(COXFE1-X)14B

被引：20

作者：

CAPEHART, TW

MISHRA, RK

HERBST, JF

机构：

[1] Physics Department, General Motors Research Laboratories, Warren

来源：

JOURNAL OF APPLIED PHYSICS | 1992年 / 72卷 / 02期

关键词：

D O I：

10.1063/1.351851

中图分类号：

O59 [应用物理学];

学科分类号：

摘要：

Using x-ray-absorption near-edge spectroscopy (XANES) the Pr valence in the pseudoternary Pr2(CoxFe1-x)14B compounds has been directly determined. Praseodymium L(III) edge XANES structures were obtained for the x=0, 0.3, 0.5, 0.7, and 1 compositions spanning the entire Co concentration range. It is found that the Pr valence is constant through the series and is identical to that in formally trivalent praseodymium acetate. The results demonstrate that the anomalous variation of the magnetocrystalline anisotropy with x in the Pr2(CoxFe1-x)14B compounds vis-a-vis their Nd-based counterparts does not arise from a Pr valence instability, as has been speculated in the literature, but must originate elsewhere. For comparison purposes XANES spectra for some relevant Ce and Nd materials are also reported.

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页码：676 / 679

页数：4

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