Comparison to XPS

Bauer and Kolaczkiewicz (1985) have investigated by low EELS the edge structures of Eu, Gd and Tb single-crystal films or atomically dispersed layers adsorbed on W (110) and W (112) surfaces. Several few intense structures and a sharp dominant loss peak at about 4 eV have been recorded. The latter has been attributed to spin exchange excitation of the 4f level. A comparison to XPS results led to a re-consideration of the interpretation of the 4f XPS binding energies. 

Many applications of XPS to problems in adhesion science have been reported in the literature. One interesting example is provided by the work of Tsai et al. on the use of XPS to investigate reactions between model rubber compound and plasma polymerized acetylene films that was discussed above [22,23], Consideration of that system permits some interesting comparisons to be made regarding the type of information that can be obtained from RAIR and XPS. 

We also compare our results to XPS data on bulk gold and on the smaller centered clustercompound Au 11L7X3 (with X = Cl or I) [74]. A comparison is also made to XPS results obtained on bare gold clusters deposited on poorly conducting substrates [75, 76]. This gives still more support to the idea of the metallic bonding of the Aujj clusters. 

A first difference between our XPS results and those of Quinten et al. is the lower statistics that our XPS spectra exhibit in comparison to theirs. The reason for the low statistics in our 5d peak lies in the relatively fast spectra acquisition deliberately used in order to prevent changes in the spectrum due to irradiation. 

A standard technique for the comparison of XPS results on bare gold clusters supported on substrates [74,75] is to relate surface coverage during deposition to average diameter of the particles formed by surface diffusion after deposition. 

This emission is considerably enhanced as compared with the spectrum of Th metal (see Fig. 9). The comparison of XPS valence band for U and Th (with a 5 f° configuration) provides a straightforward and direct identification of the 5f emission. Consequently, the strong emission for U at Ep can be attributed to itinerant 5 f states, hybrid-... 

High resolution UPS valence band spectra for thin films of Np02 and Pu02 are shown in Fig. 26 for comparison UO2 is added. In contrast to XPS results, exhibiting only an intense broad asymmetric structure near to Ep, the UPS spectra separate the oxygen (mainly 2p) valence band from the actinide 5f level (closest to Ep). From the... 

Depth profiles of matrix elements on Mn- and Co-perovskite layers of fuel cathodes have been measured by LA-ICP-MS in comparison to other well established surface analytical techniques (e.g., SEM-EDX).118 On perovskite layers at a spatial resolution of 100p.m a depth resolution of 100-200 nm was obtained by LA-ICP-MS. The advantages of LA-ICP-MS in comparison to other surface analytical techniques (such as XPS, AES, SIMS, SNMS, GD-OES, GDMS and SEM-EDX) are the speed, flexibility and relatively low detection limits with an easy calibration procedure. In addition, thick oxide layers can be analyzed directly and no charging effects are observed in the analysis of non-conducting thick layers. 

A quantitative description of oxidative phosphorylation within the cellular environment can be obtained on the basis of nonequilibrium thermodynamics. For this we consider the simple and purely phenomenological scheme depicted in Fig. 1. The input potential X0 applied to the converter is the redox potential of the respiratory substrates produced in intermediary metabolism. The input flow J0 conjugate to the input force X0 is the net rate of oxygen consumption. The input potential is converted into the output potential Xp which is the phosphate potential Xp = -[AG hoS -I- RT ln(ATP/ADP P,)]. The output flow Jp conjugate to the output force Xp is the net rate of ATP synthesis. The ATP produced by the converter is used to drive the ATP-utilizing reactions in the cell which are summarized by the load conductance L,. Since the net flows of ATP are large in comparison to the total adenine nucleotide pool to be turned over in the cell, the flow Jp is essentially conservative. 

A comparison of XPS spectra of Tb207 and TbC>2 with those of Tb4C>7 in the 5p and 4d regions enables one to deduce the presence of both trivalent and tetravalent terbium in... 

The local environments of T-atoms in SAPO materials were examined using solid-state NMR, a bulk probe, and XPS, a surface sensitive probe. T-a-tom 2 p binding energies in XPS were found to vary in a predictable fashion with changes in NMR chemical shifts. The comparison demonstrates that XPS is sensitive to variations in the second coordination sphere for T-atoms in SAPO molecular sieves. XPS was also found to give a reasonable, quantitative measure of superficial (surface) T-atom fractions thus providing information about elemental homogeneity by comparison to bulk chemical analysis. 

According to this scheme of plasma polymerization of TMS in a closed system, it is anticipated that the atomic composition of the plasma polymer should continuously change with the plasma polymerization time. Figure 13.21 depicts comparison of XPS cross-section profile of C/Si ratios for plasma polymers deposited in a flow system reactor and that in a closed system reactor. The results clearly show that a closed system plasma polymerization of TMS indeed produces a... 

AES is especially sensitive for Ught elements such as sulfur as the ionization cross section decreases with increasing atomic number in addition the number of available de-excitation chaimels increases simultaneously with Z, so that the primary excitation is dissipated into more numerous but less intense transitions . For example, one tenth of a percent of a monolayer of sulfur can be detected on a metallic surface. As a comparison with XPS results, the sensitivity for sulfur is approximately twenty times higher in AES so) moreover, if, in the presence of several elements on the surface, peak superposition occurs, the ability to vary at will the primary energy enables separation of Auger and loss peaks so avoiding ambiguities in identification. 

The reduced Co-Zn supported catalysts are air unstable. It is the matter why only the surface of the catalyst precursors (catalysts after calcination at 320 C) are studied by the XPS method. The comparison of XPS data of catalyst samples 3 and 5 (active and inactive catalysts in relation to 2,3-DHF formation, notation as in Table 1) shows that the binding energies (BE) of Si and A1 in both cases are similar to those in the pure oxides (Si2p 103.3 and 103 eV, A12p 74.7 and 74.6 eV, respectively). It points out the lack of strong interaction between Si and other elements as well as the absence (or few) of typical aluminosilicate network. The surface of active sample 3 contains more of Si than the inactive catalyst 5 (Si/Al 2.6 and 2.1, respectively). 

The coordination chemistry of second-row transition metal corroles is less extensive than for first-row metals, but there are now numerous examples. The synthesis of brick red (oxo)Mo(mec) (mec = 2,3,17,18-tetramethyl-7,8,12,13-tetraethylcorrolate) was reported in a 1977 letter [63]. The first Ru corrole was synthesized as a cofacial Ru(III)-Ru(III) dimer in 2000 [64] the synthesis of a monomeric Ru corrole was achieved in 2003 [65]. A dicarbonylrhodium(I) A -me thy I corrole complex, where Rh(I) is bound to two of the ring nitrogen atoms, was reported in 1976 [66], while the synthesis of a Rh(III) corrole was published a dozen years later [67]. A series of Ag(III) corroles was described in 2003 [68]. This oxidation state assignment was supported by an X-ray photoelectron spectroscopy (XPS) comparison to cationic Ag(III) porphyrin complexes. 

Figure 10. (A) Comparison of wet chemical and Mossbauer results on biotites. Results suggest that excellent agreement can be obtained between these techniques, even when Lorentzian line shapes are used to fit the Mossbauer spectra. (B,C) Comparison of XPS data with wet chemical (B) and Mossbauer (C) results on biotites, adapted from Raeburn et al. (1997a,b). (D,E) SmX results on Fe VSFe in micas plotted against wet chemical (D) and Mossbauer (E) data. (F) Comparison of XPS with XANES data on the same samples.

The density of states (labelled DOS theory ) for the a-quartz energy bands calculated by Chelikowsky and Schliiter (1977), compared with ultraviolet photospectroscopy ( UPS ) data obtained experimentally by Ibach and Rowe (1974c) (broken line) and DiStefano and Eastman (1971a) (dashed-dotted line), and X-ray photospectroscopy ( XPS ) data obtained experimentally by DiStefano and Eastman (1971a). A shift of 5 eV was made in the oxygen, v peak, in comparison to the bands of Fig. ll-9,a. [After Chelikowsky and Schliiter, 1977.]... 

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