The near-edge processes, such as X-ray absorption ﬁne structure (XAFS) andresonant Raman scattering (RRS), are not incorporated in the available theoretical attenuation coefﬁcients, which are known to be reliable at energies away from the shell/subshell ionization thresholds of the attenuator element. Theoretical coefﬁcients are generally used to estimate matrix corrections in routine quantitative elemental analysis based on various X-ray emission techniques. A tabulation of characteristic X-ray energies across the periodic table is provided where those X-rays are expected to alter the attenuation coefﬁcients due to XAFS from a particular shell/subshell of the attenuator element. The inﬂuence of XAFS to the attenuation coefﬁcient depends upon the atomic environment and the photoelectron wave vector, i.e., difference in energies of incident X-ray and the shell/subshell ionization threshold of the attenuator element. Further, the XAFS at a shell/subshell will signiﬁcantly alter the total attenuation coefﬁcient if the jump ratio at that shell/subshell is large, e.g., the K shell, L3 subshell and M$_5$ subshell. The tabulations can be considered as guidelines so as to know what can be expected due to XAFS in typical photon-induced X-ray emission spectrometry.
Volume 94, 2020
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