Shake-up satellite

Fig. 2. The Ols and C 1 s regions of the X-ray photoelectron spectrum of C3O2, showing the shake-up satellites. Reproduced with permission from Ref.77)...

The relative instrumental sensitivity factors for cobalt and nitrogen were determined by measuring core level (Co 2p and N Is) XPS spectra for a series of pure cobalt amine complexes of established stoichiometry. To evaluate the core level photopeak intensities, peak areas, including shake-up satellite intensity were used. The precision for the measurements of the nitrogen to cobalt atomic ratio is 10% while the accuracy is approximately 15%. Additional details of the XPS measurements are contained in the literature (24,25). 

The XPS results for cobalt at pH 4, particularly the Co 2p splitting (15 eV) and the absence of shake-up satellite structure, are indicative of cobalt(III). However, the N(amine)/Co atomic ratio of 2.7 indicates that some ammonia ligands have been displaced. Since it is known (22) that hydrolysis rates for cobalt(III) complexes are very slow, the presence of cobalt with a low number of coordinated amines, suggests that hydrolysis is induced via an interaction with the birnessite surface. The cobalt to manganese ratios for bulk and surface measurements are equivalent within experimental error, a result which is consistent with a reaction process occurring primarily at the surface. It is... 

The thermally induced interconversion of two oxides, e.g., C03O4 and CoO, and CU2O and CuO, has been followed by electron spectroscopy 15, 67). In both cases the shake-up satellites associated with the Co(2piy2)... 

In d-metals, the opposite is true the d-wavefunctions hybridize easily with conduction band states. The main peak can in this case be coordinated with the well screening outer d s, and the shake-up satellite, when observed, is due to the poorly screening process (Fig. 7c). For d-metals, furthermore, the very high density of d-states at Ep is the cause of many secondary electron excitation from just below Ep to empty states just beyond Ep which results in the asymetric high energy tailing of the main peak. Final state multiplet splitting, explained above, can in addition overlap the split response. 

There are, however, arguments, which contradict the partial localization interpretation. This interpretation must assume that the 5 f emission at Ep (itinerant state) and at the 2.5 eV satelhte have different photon energy dependence of the cross section at the resonance. As recently discussed this is difficult to explain since both structures are attributed to 5 f states. Furthermore, the main asymmetric 4 f core level should be accompanied by a shake-up satellite, induced by 6d screening of the localized hole, which has never been observed. 

If the hierarchy of information levels available in ESCA were limited to those discussed in detail in the proceeding sections the technique would clearly be extremely useful and versatile in many applications. It is evident, however, that for systems in which only a single core level is available for study and for which no chemical shifts are apparent that the range of applications of the the technique to such systems would be limited. Fortunately ESCA is a much more interesting and subtle technique and such systems are encompassed when we consider the information available from the direct study of low energy shake up satellites. 

The trend in intensities for the substituent shake up satellites is in the opposite sense to that for the Cls levels and this becomes more evident on consideration of the ratio corrected for equal numbers of atoms. (The intensity ratio for the methoxy derivative is almost certainly a lower limit since there is some evidence from the 0ls spectrum that there is a small amount of water and/or oxidation at the surface.)... 

The analysis of the shake up satellites in terms of a two component structure leads to the correlation shown in Fig. 46 where for convenience the data has been analyzed in terms of the coulomb integrals of the substituents. 

It is gratifying to note that the theoretical calculations on model systems reproduce the trends shown in Fig. 46 providing strong confirmation for the overall validity of the interpretations32 36. Low energy shake up satellite structures are often highly characteristic of the n electronic structure of the pendant group as is clear from a comparison of Fig. 43 and Fig. 47. In each case theoretical analysis indicates... 

Fig. 48. Orbitals involved in the low energy shake up satellites accompanying core ionization in polystyrene, poly-l-vinylnaphthalene and polyvinylcarbazole...

Fig. 51. Plot of ratio of area ratios for direct photoionization peak and tow energy shake up satellite for a series of alkane styrene copolymers as a function of chain length n of the alkane component...

The Cr 2p3a binding energies (XPES) increase from Cr(CNPh)6 to [Cr(CNPh)6]+ to [Cr(CNR)6]2+, the values being 574.5, 575.3 and 576.7 eV respectively.22 29 The shake-up satellite structure associated with the N Is and C Is binding energies in these spectra most probably arises from M (d)- it (CNAr(R) excitations accompanying the primary photoemission. 

The Cu(2p3/2) photoelectron and LW Auger spectra obtained from a copper mirror treated with an aqueous solution of y-APS at pH 10.4 are shown in Fig. 13. Two components were observed near 932.4 and 934.9 eV in the Cu(2p3/2) photoelectron spectrum, clearly indicating the presence of Cu(I) and Cu(II), respectively. The presence of Cu(II) was confirmed by a broad, weak shake-up satellite near 944.0 eV. 

Shake-up satellite structure in the X-ray photoelectron spectra of [Mo(CNR)7](PF6) (R = Me, Bu, C6H,) has been observed. The similarity of the nitrogen band carbon s Is/lp ratios to those of Mo(CO)6 oxygen b and carbon b Is/lp ratios argues for a similarity in bonding, as a decrease in the metal-carbon bond length (i.e., stronger M-C bonding) will influence both the satellite position relative to the primary peak and the Is/lp intensity ratio (266). 

Fig. 3.3 The relationship of the first moment of the photoelectron spectrum of a core state to the main peak and the shake-up satellite structure is illustrated21 36.

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