Spectral Structural

In SXAPS the X-ray photons emitted by the sample are detected, normally by letting them strike a photosensitive surface from which photoelectrons are collected, but also - with the advent of X-ray detectors of increased sensitivity - by direct detection. Above the X-ray emission threshold from a particular core level the excitation probability is a function of the densities of unoccupied electronic states. Because two electrons are involved, incident and the excited, the shape of the spectral structure is proportional to the self convolution of the unoccupied state densities. 

Band L, Bencini A, Benelli C, Gatteschi D, Zanchini C (1982) Spectral-Structural Correlations in High-Spin Cobalt(II) Complexes. 52 37-86 Band L, Bertini I, Luchinat C (1990) The H NMR Parameters of Magnetically Coupled Dimers-The Fe2S2 Proteins as an Example. 72 113-136 Baran EJ, see MuUer A (1976) 26 81-139... 

A certain interaction between tin and chlorine atoms through ji- and a-electron systems has been confirmed by spectral structural studies of chloroorganotin adducts and model compounds35). 

The above results of ab initio calculation for the, 431 [ state of NCN (completed by those employing hypothetical values for s and, 4so) correspond to the schematic presentation of the effect of combined vibronic and spin-orbit couplings onto the spectral structure of 3II states of linear triatomics, carried out by Hougen [32] and reproduced in Herzberg s book (see Fig. 9 and accompanied discussion in [5]). A more detailed insight can be achieved by inspecting the perturbative formulae given in Appendix A. 

Although not the central subject of this review, several thorium dihaptocarbamoyl complexes ( 4) Th(n2-CONR2)/ were also examined with respect to thorium hydride-catalyzed reduction. Under 0.75 atm H2 and over the course of several days at temperatures as high as 100°C, no hydrogenation was observed. These results are in accord with other spectral, structural, and chemical data (14) indicating the importance of carbamoyl resonance hybrids O and P, and that the carbene-like reactivity is significantly reduced in comparison to the acyls (14) ... 

De Jesus, V.L.B., B. Feuerstein, K. Zrost, D. Fischer, A. Rudenko, F. Afaneh, C.D. Schroter, R. Moshammer and J. Ullrich. J. Phys. B, 37 L161, 2004. Madronero, J. Spectral structure of planar helium under periodic driving. Ludwig-Maximilians-Universit t Miinchen, 2004. 

Spectra of a spent bauxite-based desulfurization catalyst pellet ( 7 x 13 mm, examined in air) are shown in Fig. 9. The outside of the pellet was black and the single-beam spectrum S showed some of the continuum absorption found with chars. The compensated spectrum S/So, however, showed appreciable spectral structure. The broad band near 750 cm is probably due to the bauxite, and the absorptions near 3000, 1320 and 1000 cm-- - to a mixture of hydrocarbons and thio species formed during the reaction. The feature near 1640 cm l is probably caused by an olefinnic species. 

As an example for the use of mass spectral features we look at a mass spectral-structure relationship. It is known that for some substance classes, the degree of... 

Band, L., Bencini, A., Benelli, C., Gatteschi, D., Zanchini, C. Spectral-Structural Correlations in High-Spin Cobaltfll) Complexes. Vol. 52, pp. 37-86. 

With this technique the Doppler width could be reduced by two orders of magnitude below the natural linewidth, and spectral structures within the Doppler width could be resolved. Examples are the resolution of hyperfine structure components in an 12-beam using a single-mode argon laser (tunable within a few gigahertz) or the investigation of the upper state hfs-splitting in the atomic... 

Extended X-ray absorption fine structure (EXAFS) refers to the fine spectral structure found in the absorption coefficient at wavelengths 0.1-0.2 beyond the... 

If we know that the instrument response is band limiting with frequency cutoff Q, we may likewise process the estimate. The resulting solution will then also be band limited. The high-frequency spectral structure beyond cutoff Q that we would wish to restore is forever lost to these linear methods. The data contain no information about the high-frequency content. We must wait until Chapter 4 to see how straightforward and seemingly unimportant... 

The carbon ls1/2 transition was observed in a sample of polyester film at near 1195 eY. The raw data indicate the presence of the three different carbon sites in the polyester molecule. The deconvolved data reveal additional spectral structure (Fig. 7). The additional structure appears in the form of a threefold repetition of the same curve. We easily reproduced the... 

The complex spectral structure from 750 to 650 cm."1 was resolved mathematically by Binder into a series of overlapping bands of the theoretical Lorentz shape (3). It was shown that only the band at 740 cm."1 originated in the cis-olefin group. However, measurements on... 

Indole in cyclohexane and ethanol is excited at 270 nm populating a mixture of the La and Lb states. The La and Lb states differ in their spectral structure (Fig. la)) and Stokes shifts [3]. The unstructured spectrum of the La state shows a large Stokes shift due to the large change of the dipole moment upon electronic excitation. The dipole moment of the Lb state is similar to the ground state value. In nonpolar solvents like cyclohexane, the Lb state is energetically below the La state and its emission spectrum exhibits vibronic structure. In the polar solvent ethanol state reversal occurs after the electronic excitation and the La state becomes responsible for the more red shifted fluorescence [4],... 

Among the absorption spectrum of relatively simple polyatomic molecules, a spectral structure of the strong 1E+-IE+ band of OCS in the 160-140-nm region [5] is noteworthy. Though there is a broad background-like structure in the entire absorption band, there are seven distinct features with a sep-... 

The arc and spark spectra in the ultra-violet region have also been photographed and measured.8 The spectral structure of niobium resembles that of vanadium, and various regularities have been discovered in it.4 In order to be able to establish speetrographically the... 

Systems of Spectral Structures for Ten Elements of the Fourth Period (a) Arc Spectra, Neutral Atoms... 

The numbers 1, 2, 3, 4, etc., represent the maximum multiplicities in the spectral terms or atomic energy levels belonging to the corresponding systems of spectral structures, singlets, doublets, triplets, quartets, etc. Those in parentheses, still unknown, are suggested from considerations of symmetry. 

Visualization of results, their statistical validity, and analysis of results are becoming increasingly important. Several techniques are available to represent data and compact representations are increasingly being made by images. The ease of visualization, however, must always be tempered with the need to present data completely and in an accurate manner. In particular, two areas are of relevant important. The first is two-dimensional spectral representation to better understand spectral structure while the second is more useful for imaging. 

The close aromaticity values for AAphosphinine, pyridine, and benzene according to spectral, structural, theoretical, and energetic criteria are discussed in detail in Nyulaszi s review [214],... 

Numerous studies about phases and phase transitions detected by optical investigations of f elements have been published by Haire, Peterson, and co-workers. In many cases they used the Eu3+ ion to correlate the luminescence properties with structural changes. The Eu3+ ion exhibits a variety of characteristic transitions serving as a fingerprint for the structure (Chen et al., 1992e). However, in view of the problematic situation with respect to the local symmetry in the case of doped ions mentioned above, there has been some discussion on whether the Eu3+ ion or f elements in general can be used as indicators of the actual host structure or not (Tanner and Rudowicz, 1993 Stump et al., 1993). In summary, it must be concluded that the spectral/structural correlation has limitations especially in the case of doped ions where deviations between local and real site symmetry may readily occur. 

D. Gatteschi, C. Zanchini Spectral-Structural Correlations in High-Spin Cobalt (II) Complexes. - A. Tressaud, J.-M. Dance Relationships Between Structure and Low-Dimensional Magnetism in Fluorides. - V.KJain, R.Bohra, R.C.Mehrotra Structure and Bonding in Organic Derivatives of Antimony (V). 

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