Satellite intensity distributions

In photoelectron. Auger and X-ray spectroscopies, the frozen core and sudden approximations have frequently been used for their simplicity. However, interesting chemical bond effects in Auger and X-ray spectra have not yet been explained by such over simplified approximations. The representatives are remarkable changes in satellite intensity distributions appeared in X-ray and Auger spectra emitted from a series of fluorides [14-20], Introduction of a new concept of... 

Satellite Intensity Distributions Written in the Atomic Frame... 

To evaluate the thermodynamic and radiation properties of a natural or perturbed state of the upper atmosphere or ionosphere, the thermal and transport properties of heated air are required. Such properties are also of particular interest in plasma physics, in gas laser systems, and in basic studies of airglow and the aurora. In the latter area the release of certain chemical species into the upper atmosphere results in luminous clouds that display the resonance electronic-vibrational-rotational spectrum of the released species. Such spectra are seen in rocket releases of chemicals for upper-atmosphere studies and on reentry into the atmosphere of artificial satellites. Of particular interest in this connection are the observed spectra of certain metallic oxides and air diatomic species. From band-intensity distribution of the spectra and knowledge of the /-values for electronic and vibrational transitions, the local conditions of the atmosphere can be determined.1... 

Figure 15 Neutron time-of-flight study of 0-(BEDT-TTF)2I3 performed at the IPNS pulsed source (Argonne). (a) Neutron diffraction intensity distribution in the h = 4.92 reciprocal lattice plane at 20 K and ambient pressure. Satellite peaks are observed (arrows) (b) the same reciprocal plane after applying a pressure of 0.14 GPa, warming to room temperature, and cooling back down to 20 K. (From Ref. 64.)...

A theoretical interpretation of the core-level satellite structure in the x-ray photoemission spectrum was also offered by Messmer et al./134/ using a larger CugCO cluster and assuming the chemisorption of CO in the one-fold and fourfold sites of the Cu (100) surface. The qualitative differences in the intensity distributions suggest that the CugCO cluster is a better model than the smaller Cu5CO cluster for the Cu (100) surface. 

Fig. 18. Franck-Condon progressions, (a) The equilibrium positions of the potential surfaces of the excited state II and the ground state 0 are shifted by AQ. This leads to a progression, if the dipole moment of the transition between the states II and 0 is non-zero. The progression is characterized by vertical transitions that are depicted for a low-temperature emission, (b) The intensity distribution of a progression of vibrational satellites depends on the Huang-Rhys parameter S which is proportional to (AQ) (see Eq. (12)). The examples given in (b) are calculated according to Eq. (13). The peaks of highest intensity are normalized for the different diagrams. It is marked that the maximum Huang-Rhys parameter for Pd(2-thpy)2 and Pt(2-thpy)2 have been determined to = 0.3 and = 0.08, respectively. (Compare also Sect. 4.2.4)...

The vibrational satellite structure corresponding to the emission of the electronic state I is distinctly altered due to the perdeuteration. As expected (Sect. 4.2.10.1), all vibrational frequencies are red shifted, apart from the phonon satellite of 15 cm h However, by using the intensity distributions of the vibrational satellites, it is possible to correlate many of the vibrational modes of the perprotonated to those of the perdeuterated compound, as is carried out in Fig. 25. 

Fine structures of photoelectron. Auger electron and X-ray spectra emitted from molecules through the transition from valence to inner-shells are sensitive to the change in chemical environments surrounding the atom of interest, and then have been used extensively for studies of electronic structures of chemical compounds[l-9]. For obtaining these spectra, photons, electrons and accelerated ions have been employed as excitation sources. However different kinds of excitation methods make explanations of the fine structures and/or satellite structures of Auger and X-ray spectra complicated. This is a main cause why intensity distributions of these spectra can not be discussed quantitatively. 

Methods for estimating intensity distributions of X-ray satellite spectra induced by accelerated ions with energies of a few MeV/amu are reviewed, where the orbitals responsible for X-ray emission are written in the molecular frame, not in the atomic frame. 

Generally, for light ion impacts, the observed intensity distributions of satellite structures or finger patterns can be reproduced by eq. (6). Shown in Fig. 2 are examples for the impact of on K and Cr, and the impact of... 

The observed satellite structure intensity distributions for heavy ion (Z 6) impacts such as and O on K and Cr are shown in Fig.4. 

The present author proposed an the approximation method to explain the deviation of the X-ray satellite spectra intensity distributions from those described by eqs.(2),(5),(8) and (10), which we call Resonant Orbital Rearrangement (ROR) [6]. ROR was first used to explain the anomalous intensity distributions in F Ka satellite spectra which are emitted from a series of alkali-fluorides. Here resonance occurs during F Is ionization between the highest occupied molecular orbital (HOMO) in the KT. state and HOMO in the (K L +3s) state corresponding to the lowest unoccupied molecular orbital (LUMO) in the K L state. This leads to a reduction in the K L X-ray satellite intensity and to an increase in the K L X-ray diagram line intensity. Here (K L +3s) denotes the state with one vacancy in K shell and one vacancy in L shell and one electron in a 3s... 

Typical photon induced X-ray spectra, emitted from NaF, KF, RbF and CsF, are shown in Fig.l3. The intensity distributions of these spectra can be explained by taking only the shake and ROR processes into account, because they are free from the satellite X-rays emitted through the direct Coulomb ionization. Then photon induced satellite spectra can be used, in the following manner, to estimate the ion-induced or particle induced X-ray satellite intensities without any complicated calculations. This is because the excitation process in particle induced X-ray emission (PIXE) can be described by a snperposition of the direct Coulomb, the shake and ROR processes. Here the shake and ROR processes are common to both photon- and particle- induced X-ray emission spectra, allowing utilization of the same ROR probability to explain both spectra. 

The molecular structure of XeOF4 is a square pyramid with the 0-atom residing at the apical position (see structure 8). The four fluorine atoms are located at the equatorial positions in a basal plane. Because of the equivalency of the fluorine atoms, only one resonance is expected. Because of the interactions between fluorine and the isotopes of Xe ( Xe (spin = Yi abundance 26.4%) and Xe (spin = 3/2 abundance 21.1%)) we do expect two additional weak features. So the predicted spectra will consist of a central line and two other lines, called satellites, symmetrically distributed around this central line. One set of satellites is due to the coupling between F and Xe nuclei and would be a doublet. The other set is due to the coupling between and Xe nuclei and would be a non-binomial quartet (four lines of equal intensity). 

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