Infrared reflectance-absorption spectroscopy

KJ. Uram, L. Ng, and J.R.Yates Jr., Electrostatic effects between adsorbed species-The K-CO interaction on Ni(lll) as studied by infrared reflection - absorption spectroscopy, Surf. Sci. 177, 253-277 (1986). 

Recent work in our laboratory has shown that Fourier Transform Infrared Reflection Absorption Spectroscopy (FT-IRRAS) can be used routinely to measure vibrational spectra of a monolayer on a low area metal surface. To achieve sensitivity and resolution, a pseudo-double beam, polarization modulation technique was integrated into the FT-IR experiment. We have shown applicability of FT-IRRAS to spectral measurements of surface adsorbates in the presence of a surrounding infrared absorbing gas or liquid as well as measurements in the UHV. We now show progress toward situ measurement of thermal and hydration induced conformational changes of adsorbate structure. The design of the cell and some preliminary measurements will be discussed. 

K. and Enyo, M. (1989) Surface species produced on Pt electrodes during HCHO oxidation in sulfuric add solution as studied by infrared reflection-absorption spectroscopy (IRRAS) and differential electrochemical mass spectroscopy (OEMS)./. Electroanal. Chem., 258, 219-225. 

Watanabe, S., Inukai, J. and Ito, M. (1993) Coverage and potential dependent CO adsorption on Pt(llll), (711) and (100) electrode surfaces studied by infrared reflection absorption spectroscopy. Surf. Sci., 293, 1-9. 

Figure 6.16 Attenuated total reflection surface enhanced infrared reflection absorption spectroscopy (ATR-SEIRAS) spectra for the oxidation of 0.1 M HCOOH in 0.5 M H2SO4 on a polycrystaUine electrode. The bands at 2055 -2075 and 1800-1850 cm are assigned to linear- and bridge-bonded CO, whereas the band at 1323 cm corresponds to adsorbed formate. (Reproduced from Samjeske et al. [2006].)...

Bhzanac BB, Arenz M, Ross PN, Markovic NM. 2004b. Surface electrochemistry of CO on reconstructed gold single crystal surfaces studied by infrared reflection absorption spectroscopy and rotating disk electrode. J Am Chem Soc 126 10130-10141. 

Watanabe M, Zhu Y, Uchida H. 2000. Oxidation of CO on a Pt-Fe alloy electrode studied by surface enhanced infrared reflection-absorption spectroscopy. J Phys Chem B 104 1762-1768. 

The three most commonly applied external reflectance techniques can be considered in terms of the means employed to overcome the sensitivity problem. Both electrically modulated infrared spectroscopy (EMIRS) and in situ FTIR use potential modulation while polarization modulation infrared reflection absorption spectroscopy (PM-IRRAS) takes advantage of the surface selection rule to enhance surface sensitivity. 

Some characteristics of, and comparisons between, surface-enhanced Raman spectroscopy (SERS) and infrared reflection-absorption spectroscopy (IRRAS) for examining reactive as well as stable electrochemical adsorbates are illustrated by means of selected recent results from our laboratory. The differences in vibrational selection rules for surface Raman and infrared spectroscopy are discussed for the case of azide adsorbed on silver, and used to distinguish between "flat" and "end-on" surface orientations. Vibrational band intensity-coverage relationships are briefly considered for some other systems that are unlikely to involve coverage-induced reorientation. 

SERS) (1) and several variants of infrared reflection-absorption spectroscopy (IRRAS) (2). ... 

The combination of surface enhanced Raman scattering (SERS) and infrared reflection absorption spectroscopy (IRRAS) provides an effective in-situ approach for studying the electrode-electrolyte interface. The extreme sensitivity to surface species of SERS is well known. By using polarization modulation of the infrared beam for IRRAS, the complete band shape is obtained without modulating the electrode potential. 

Infrared drying, ceramics processing, 5 656 Infrared dyes, 9 500 Infrared emission spectroscopy, 23 142 Infrared inks, 14 315 Infrared lasers, 22 180 Infrared LEDs, 22 175, 176 Infrared measurements, in growing amorphous silicon, 22 130 Infrared microspectroscopy, 16 486 Infrared reflection-absorption spectroscopy (irras), 24 72, 114-116. See also IR spectra... 

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