Resonant emission spectra ofYF3,YCl3,

Abstract

Resonant emission spectra of YF 3 , YCl 3 , Y 2 O 3 , and Y-metal are observed across Y L III absorption threshold. When the incident photon energy is below the absorption threshold, only Raman scattering component is observed. The Raman-scattering component has a two-peak structure, main and subpeaks. Above the absorption threshold, both Raman and normal L ␣ emission peaks are observed in insulator samples. The intensities of the Raman peak are resonantly enhanced as the incident photon energy reaches the absorption edge. On the other hand, in Y metal, only normal L ␣ emission peak is observed. Obtained spectra are decomposed into Raman and normal L ␣ emission peaks by line-shape analysis. The results are compared with theoretically calculated ones and are discussed the relaxation of core-electron excitation processes. The onset energy of the normal L ␣ emission peak is estimated and discussed in relation of the electronic structure of these compounds.

Contribution of near-edge processes to attenuation of the characteristic X-rays in elements with 48≤Z≤83

“…Further, the evolution of the fluorescence process from the radiative RRS has been evidently investigated by Nakai et al [18] using monochromatic synchrotron radiation with the energy tuned across the L 3 absorption threshold of 39 Y. The investigations included the measurement of resonant emission photon spectra along with the XAS for 39 Y in metallic and insulator compound forms.…”

“…1b. The near-edge processes, RRS [15][16][17][18] and XAFS [19][20][21][22][23], have been investigated mostly using the tunable synchrotron sources. These processes contribute significantly to attenuation near the ionization threshold (Fig.…”

Influence of near-edge processes in the elemental analysis using X-ray emission-based techniques

“…Energy (E in ) Shell/subshell (keV) [27] K-shell X-rays 11 The XAFS effects can be avoided when the measurements are performed using elements in the form of monoatomic gas. In view of the jump ratio values for various shell/subshells, the limiting values for the L i (i = 1-3) subshells, D L i lim , are taken to be 20, 30 and 50, respectively, and that for the M i (i = 1-5) subshells, the D M i lim , are taken to be 20, 20, 20, 30 and 50, respectively.…”

“…These processes depend on the density of electronic states, molecular bonding and other solid-state properties of the attenuator element. With the availability of intense tuneable synchrotron sources with resolution better than 1 eV, the RRS and XAFS processes have received major impetus in recent years and are emerging as rich diagnostic tools for condensed matter systems [6][7][8][9][10][11]. The RRS process exhibits resonant behaviour for the incident photon energy (E in ) approaching an inner shell/subshell ionization threshold (B i ) of the atom from lower vicinity.…”

“…The solid-state effects on RRS were studied by various investigators [9][10][11] using tuneable synchrotron source. Nakai et al [11] measured the radiative emission spectra across the L 3 The K shell electron from the lower energy tail of Lorentzian profile is excited above the Fermi level (E F ) resulting in a virtual K shell hole state. Its typical decay channels, viz., the radiative K-L 2 and Auger KL 1 M 4 resonant Raman scattering are shown.…”