Direct determination of praseodymium valence in Pr2(Co x Fe1− x )14B

Using x-ray-absorption near-edge spectroscopy (XANES) the Pr valence in the pseudoternary Pr2(CoxFe1−x)14B compounds has been directly determined. Praseodymium LIII 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 …