Vibrational surface spectrum

I. A nine-dimensional ab initio surface, vibrational spectra and dynamics J. Chem. Phys. 103 8372-90... 

Dynamical Study of CH Overtones in Fluoroform. I. A Nine-Dimensional Ab Initio Surface, Vibrational Spectra and Dynamics. 

First, surface-sensitive techniques that can operate under technologically relevant conditions, i.e., at least in the 1 —lOOOmbar pressure range, are required. In this respect, photon-based techniques such as sum frequency generation (SFG) and polarization-modulation IR reflection absorption spectroscopy (PM-IRAS) provide surface vibrational spectra of adsorbates from UHV up to atmospheric pressure. Although electron spectroscopies are typically limited to pressures <10 mbar, recent developments in XPS allow the determination of... 

Fig. 15.12 Methanol oxidation on Pd-Al O (mean particle size 6 nm) and Pd(lll) [27, 50, 75]. (a) In situ steady-state PM-IRAS and SFG spectra, shown together with the CHjOH conversion as monitored by gas chromatography, (b) Comparison of Pd3d XP spectra obtained before upper) and after (lower) the methanol oxidation reaction indicated a partial oxidation of Pd nanoparticles during the reaction, whereas Pd(lll) remained metalhc adapted in part from [75] with permission. Copyright (2007) The PCCP Owner Societies, (c) PM-IRAS (p-s) surface vibrational spectra measured during CH OH decomposition on Pd(lll) at 300 K, with the various species indicated. The time-dependent evolution of CH O (as observed by PM-IRAS) and of CH (values deduced from XPS) upon methanol decomposition at -lO mbar suggests a correlation between the two species adapted in part from [27] with permission. Copyright (2005) American Chemical Society, (d) Suggested mechanism of CH OH decomposition and oxidation on Pd catalysts reprinted [50] with permission. Copyright (2007) Elsevier...

Electrochemical Stark Effect and the Influence of a Solvent Surface vibrational spectra of adsorbed species on an electrode are often characterized by... 

Hydrogen and deuterium composition profile Vibrational spectra of polymer surface adjacent to ATR-crystal surface Vibrational spectra of thin films and absorbed layers... 

We now present one of the many examples of interfacial vibrational spectroscopy using SFG. Figure Bl.5.15 shows the surface vibrational spectrum of the water/air interface at a temperature of 40 °C [83]. Notice that... 

Recently, an alternative assignment of the modes has been put forward for the surface vibrational spectrum ofwater. The focus is again on the band which occurs between 3000-3600 cm where the vibrational coupling (intramolecular) between the stretch and the bending overtone contribution to the spectrum has been suggested instead of structural effects. ... 

Dubai H-R, Ha T-K, Lewerenz M and Quack M 1989 Vibrational spectrum, dipole moment function, and potential energy surface of the CH chromophore In CHXg molecules J. Chem. Phys. 91 6698-713... 

Thomas GE, Weinberg WH. 1979. The vibrational spectrum and adsorption site of CO on the Ru(OOOl) surface. J Chem Phys 70 1437. 

A substantial number of electrons are elastically scattered, and this gives rise to a strong elastic peak in the spectrum. When an electron of low energy (2-5 eY) approaches a surface, it can be scattered inelastically by two basic mechanisms, and the data obtained are dependent upon the experimental geometry - specifically the angles of the incident and the (analysed) scattered beams with respect to the surface (0 and 02 in Figure 5.47). Within a certain distance of the surface the incident electron can interact with the dipole field associated a particular surface vibration, e.g. either the vibrations of the surface atoms of the substrate itself, or one or other... 

Despite the enormous impact that scanning probe methods have had on our understanding of reactions at oxide surfaces, both STM and AFM suffer from the lack of chemical specificity. The application of STM-inelastic electron tunneling spectroscopy is a potential solution as it can be used to measure the vibrational spectrum of individual molecules at the surface [69, 70]. 

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