Metals surface studies

Benard, 1983] J. Benard, Adsorption on Metal Surface, Studies in Surface Science and Catalysis 13, p. 150, Elsevier Sd. Pub. Co., Amsterdam, (1983). 

Hensley, J. W., A. O. Long, and J. E. Willard Reactions of Ions in Aqueous Solution with Glass and Metal Surfaces. Studies with Radioactive Tracers. Ind. Eng. Chem. 41, 1415 (1949). 

Further evidence that it is a step mediated channel responsible for the indirect dissociation on the W(1 0 0) surfaces comes from a comparison with the results for the step mediated dissociation on Pt(5 3 3) (Section 3.2) which exhibit very similar dynamical characteristics. A similar mechanism is likely to be responsible for the indirect dissociation channel on Ni(9 9 7) [89] (Fig. 25)., Y0 decays with Ei over the range 0 < Tq(meV) < 150 on all of the metal surfaces studied where steps are suggested to be responsible for indirect dissociation. S0 is also rather insensitive to 7 s in all cases, and, S (0n) exhibits precursor type dependencies. 

Electrochemical methods can also be used for obtaining analytical information on porous materials. Voltammetric methods and related techniques have been largely used to acquire information on reaction mechanisms for species in solution phase, whereas impedance techniques have been extensively used in corrosion and metal surface studies. In the past decades, the scope of available methods has been increased by the development of the voltammetry of microparticles (Scholz et al., 1989a,b). This methodology, conceived as the recording of the voltammetric response of a solid material mechanically transferred to the surface of an inert electrode, provides information on the chemical composition, mineralogical composition, and speciation of solids (Scholz and Lange, 1992 Scholz and Meyer, 1994, 1998 ... 

The fact that there was no CO desorption from COj/K/Agdll) was contrary to the observations on most other transition metal surfaces studied such as K/Rh(lll), K/Pd(lll),... 

In spite of the lengthy cleaning procedures involved, a growing number of rare earth metal surface studies is done on foils and even on single crystals. The mechanically polished foils or spark cut crystals are first of all degreased in an ultrasonic bath using ethanol or acetone. Afterwards they are mounted on a sample holder, but provision has to be made for sample heating. 

Eichler A, Hafner J, Gross A, Schefller M (1999) Rotational effects in the dissociation of Hz on metal surfaces studies by ab initio quantum-dynamics calculations. Chem Phys Lett 311 1... 

B. A. Ivarsson, P. Hegg, K. I. Lundstrom, U. Jonsson, Adsorption ef proteins on metal surfaces studied by ellipsometric and capacitance measurements. Colloids Surf., 1985, 13, pp. 169-192. 

Since scanning tunneling microscopy requires flat conducting surfaces, it is not surprising that most of its early application was to study inorganic materials [17, 19, 20, 29-34]. These studies include investigations of catalytic metal surfaces [24, 35-37], silicon and other oxides [21], superconductors [38], gold... 

If a surface, typically a metal surface, is irradiated with a probe beam of photons, electrons, or ions (usually positive ions), one generally finds that photons, electrons, and ions are produced in various combinations. A particular method consists of using a particular type of probe beam and detecting a particular type of produced species. The method becomes a spectroscopic one if the intensity or efficiency of the phenomenon is studied as a function of the energy of the produced species at constant probe beam energy, or vice versa. Quite a few combinations are possible, as is evident from the listing in Table VIII-1, and only a few are considered here. 

Alkanethiols and other sulfur-bearing hydrocarbons covalently attach to metal surfaces alkanethiol onto gold is the most widely studied of these systems [27-29,31,32,45]. These SAMs are ordered provided the alkane chain contains nine or more carbons [32]. Binary solutions of two alkanethiols also appear... 

Diehl R D and McGrath R 1996 Structural studies of alkali metal adsorption and coadsorption on metal surfaces Surf. Sc/. Rep. 23 43... 

For example, energy transfer in molecule-surface collisions is best studied in nom-eactive systems, such as the scattering and trapping of rare-gas atoms or simple molecules at metal surfaces. We follow a similar approach below, discussing the dynamics of the different elementary processes separately. The surface must also be simplified compared to technologically relevant systems. To develop a detailed understanding, we must know exactly what the surface looks like and of what it is composed. This requires the use of surface science tools (section B 1.19-26) to prepare very well-characterized, atomically clean and ordered substrates on which reactions can be studied under ultrahigh vacuum conditions. The most accurate and specific experiments also employ molecular beam teclmiques, discussed in section B2.3. 

Wu M-C, Estrada C A, Corneille J S and Goodman D W 1996 Model surface studies of metal oxides adsorption of water and methanol on ultrathin MgO films on Mo(IOO) J. Chem. Phys. 96 3892... 

The polarization dependence of the photon absorbance in metal surface systems also brings about the so-called surface selection rule, which states that only vibrational modes with dynamic moments having components perpendicular to the surface plane can be detected by RAIRS [22, 23 and 24]. This rule may in some instances limit the usefidness of the reflection tecluiique for adsorbate identification because of the reduction in the number of modes visible in the IR spectra, but more often becomes an advantage thanks to the simplification of the data. Furthenuore, the relative intensities of different vibrational modes can be used to estimate the orientation of the surface moieties. This has been particularly useful in the study of self-... 

Wang P-K, Slichter C P and Sinfelt J FI 1984 NMR study of the structure of simple molecules adsorbed on metal surfaces C2FI2 on Pt Phys. Rev. Lett. S3 82-5... 

Our intention is to give a brief survey of advanced theoretical methods used to detennine the electronic and geometric stmcture of solids and surfaces. The electronic stmcture encompasses the energies and wavefunctions (and other properties derived from them) of the electronic states in solids, while the geometric stmcture refers to the equilibrium atomic positions. Quantities that can be derived from the electronic stmcture calculations include the electronic (electron energies, charge densities), vibrational (phonon spectra), stmctiiral (lattice constants, equilibrium stmctiires), mechanical (bulk moduli, elastic constants) and optical (absorption, transmission) properties of crystals. We will also report on teclmiques used to study solid surfaces, with particular examples drawn from chemisorption on transition metal surfaces. 

NakatsujI H, Nakal H and Fukunishi Y 1991 Dipped adcluster model for chemisorptions and catalytic reactions on a metal surface Image force correction and applications to Pd-02 adclusters J. Chem. Phys. 95 640-7 NakatsujI H and Nakal H 1992 Dipped adcluster model study for the end-on chemisorption of O2 on an Ag surface Can. J. Chem. 70 404-8... 

Kruger S and Rdsch N 1994 The moderately-large-embedded-cluster method for metal surfaces a density-functional study of atomic adsorption J. Phys. Condens Matters 8149... 

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