ARUPS

PD (covers a variety of other acronyms, like ARPEFS, ARXPD, ARXPS, ARUPS, NPD, OPD, PED) yes 88 7.9... 

Some of the techniques in Tab. 1.1 have angle-resolved variants, witli die prefix AR, e. g. ARUPS, or use Fourier transform mediods, with die prefix FT, e. g. FT-RAIRS. 

I, Thf plate of Eiiciilyptua arups/i/afiita of Labillardier in his Pla[Pg.347]

D Whlttleton, MA, CEng, MlMechE, MHKIE Ove Arup Partners, Industrial Division... 

Fig. 8.41 Permeation cell using battery technology (after Arup")...

Arup and Partners, Electropotential Mapping of Corrosion in Concrete, HMSO (OTH 88286)... 

ARUPS Angle Resolved Ultraviolet Photoelectron Spectrometry... 

Figure 3. ARUPS energy distribution curves taken with Hel radiation at normal incidence and an electron emission angle of 52" shown as a function of copper coverage. The intensity of the various curves has been normalized at the Fermi level Ef The individual curves are matched to their corresponding copper coverages in monolayers by the solid lines and the saturation behavior of the interface state at approximately —1.5 eV is identified by the dashed lines. (Data from ref. 8.) (Reprinted with permission from ref. 43. Copyright 1987 American Association for the Advancement of Science.)...

ARUPS results have identified unique electronic interface states for the Cu/Ru(0001) system. These states are not present in either metal separately but exist because of the abrupt change in properties at the interface. 

The cells shown in Figs. 28 and 29 all operate according to the same principles, which have been developed by Arup. The interior of the cell acts as the anode chamber, and a metal oxide cathode placed inside the cell in an alkaline electrolyte acts as the counter electrode. The hydrogen flux across the integrated membrane (coated with palladium on the internal surface) can be measured as the potential drop across a resistor placed between the membrane and the counter electrode. 

H Arup, in 9th Scandinavian Corrosion Congress, Korrosionscentralen ATV, Glostrup, Denmark, 1983, p. 825. 

H Arup, in 10th Scandinavian Corrosion Congress, Swedish Corrosion Institute, Stockholm, 1986, p. 1. 

C. Christensen, H. Arup, P. Press, andP. B. Mortensen, in Hydrogen Transport Cracking in Metals, Ed. by A. Turnbull, Institute of Materials, London, 1995, p. 161. 

Figure6.6. (a) ARUPS spectra(F 150K,n 20eV)ofTTF-TCNQalongthe chain direction. The dashed line outlines the dispersion of the main spectral feature, (b) ARUPS spectra along the perpendicular a-direction. (c) Selected spectra from (a), after background subtraction. The asterisks mark the main dispersive peak, and the arrows mark emission not accounted for by band theory. Energies are referred to E-p, determined to 1 meV accuracy on an evaporated, polycrystalline silver film. Reprinted with permission from F. Zwick, D. Jdrome, G. Margaritondo, M. Onellion, J. Voit and M. Grioni, Physical Review Letters, 81, 2974 (1998). Copyright (1998) by the American Physical Society.

Astonishingly, the same ARUPS spectra have been observed for ex situ grown TTF-TCNQ thin films (Rojas et al, 2001). The hlms were obtained by thermal sublimation in HV ( 10 mbar) on cleaved KCl(lOO) substrates and consisted of highly oriented and strongly textured rectangular-shaped microcrystals as shown in the TMAFM image of Fig. 6.9. The molecular afc-planes are parallel to the substrate surface and the microcrystals are oriented with their a- and fc-axis parallel to the [110] and [110] substrate directions, respectively, due to the cubic symmetry of the substrates. ARUPS spectra taken on the as-received hlms, measured along the substrate equivalent [100] direchons at T 100 K, are shown in Fig. 6.10. 

Figure 6.8. ARUPS spectra measured for k along the F-Z direction T 61 K, 25 eV). The energy and angular resolution amounted to 60 meV and 1°, respectively. The thin lines indicate the dispersion of the spectral features. Reprinted with permission from R. Claessen, M. Sing, U. Schwingenschlogl, P. Blaha, M. Dressel and C. S. Jacobsen, Physical Review Letters, 88, 096402 (2002). Copyright (2002) by the American Physical Society.

Figure 6.10. ARUPS spectra taken on a TTF-TCNQ thin fllm at F 100 K and with 21.2 eV photons along the directions bisecting both a- and -directions (polar angles 0 are shown). A parabolic background has been subtracted to enhance the features. Reprinted from Surface Science, Vol. 482 85, C. Rojas, J. Caro, M. Grioni and J. Fraxedas, Surface characterization of metallic molecular organic thin films tetrathiafulvalene tetracyanoquinodimetane, 546-551, Copyright (2001), with permission from Elsevier.

As indicated above, the ARUPS results were all taken at cryogenic temperatures. In fact the TTF-TCNQ energy band dispersion cannot be observed at RT because of the considerable vibration of the surface molecules in UHV. These surface thermal vibrations, facilitated by the weak intermolecular interactions, should induce a reduction of q at the surface. Indeed, if we model the ID energy dispersion of the TTF HQMQ and TCNQ LUMQ bands using Eq. (1.33), then we obtain ... 

ARUPS Angle-Resolved Ultraviolet Ptiotoelectron Spectroscopy... 

UPS and XPS (Ultraviolet and X-Ray Photoemission Spectroscopy) and ARUPS (Angle-Resolved UPS)... 

The computational effort is larger in ARUPS than in LEED, since more physical processes are involved, so that for the limited purpose of surface crystallography LEED seems more appropriate. Furthermore, ARUPS is best done with synchrotron radiation, which limits its availability. 

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