Department of Physics and Astronomy, University of Waterloo, Waterloo, N2L 3G1, Canada.
Sci Rep. 2011;1:182. doi: 10.1038/srep00182. Epub 2011 Dec 6.
An alternative measure of x-ray absorption spectroscopy (XAS) called inverse partial fluorescence yield (IPFY) has recently been developed that is both bulk sensitive and free of saturation effects. Here we show that the angle dependence of IPFY can provide a measure directly proportional to the total x-ray absorption coefficient, µ(E). In contrast, fluorescence yield (FY) and electron yield (EY) spectra are offset and/or distorted from µ(E) by an unknown and difficult to measure amount. Moreover, our measurement can determine µ(E) in absolute units with no free parameters by scaling to µ(E) at the non-resonant emission energy. We demonstrate this technique with measurements on NiO and NdGaO(3). Determining µ(E) across edge-steps enables the use of XAS as a non-destructive measure of material composition. In NdGaO(3), we also demonstrate the utility of IPFY for insulating samples, where neither EY or FY provide reliable spectra due to sample charging and self-absorption effects, respectively.
一种称为反部分荧光产率（IPFY）的 X 射线吸收光谱学（XAS）的替代测量方法最近已经开发出来，它既具有整体敏感性又没有饱和效应。在这里，我们表明 IPFY 的角度依赖性可以提供与总 X 射线吸收系数µ（E）直接成正比的测量。相比之下，荧光产率（FY）和电子产率（EY）光谱由于未知且难以测量的量而与µ（E）偏移和/或失真。此外，我们的测量可以通过与非共振发射能量处的µ（E）进行缩放来以绝对单位确定µ（E），而无需任何自由参数。我们通过在 NdGaO（3）上进行的测量来证明该技术。确定边缘台阶处的µ（E）使得 XAS 能够用作材料成分的非破坏性测量。在 NdGaO（3）中，我们还证明了 IPFY 对于绝缘样品的实用性，由于样品充电和自吸收效应，EY 或 FY 都无法提供可靠的光谱。
