Solution, Fourier-transform infrared spectroscopy

O Faix. Characterization in Solution Fourier Transform Infrared Spectroscopy, bi SY Lin and C Dence, eds. Methods in Lignin Chemistry. Berbn Springer-Verlag, 1992, pp. 233-241. 

The structure of poly(iminocarbonates) synthesized by the direct interfacial polymerization of BPA and cyanogen bromide was analyzed by NMR, Fourier transform infrared spectroscopy and elemental analysis and found to be identical in all aspects to authentic poly(imino-carbonates) obtained by solution polymerization (46). 

Subtractively normalized interfacial Fourier transform infrared spectroscopy (SNIFTIRS), has been used extensively to examine interactions of species at the electrode/electrolyte interface. In the present work, the method has been extended to probe interactions at the mercury solution interface. The diminished potential dependent frequency shifts of species adsorbed at mercury electrodes are compared with shifts observed for similar species adsorbed at d-band metals. 

Subtractively normalized interfacial Fourier transform infrared spectroscopy has been used to follow the reorientations of isoquinoline molecules adsorbed at a mercury electrode. Field induced infrared absorption is a major contribution to the intensities of the vibrational band structure of aromatic organic molecules adsorbed on mercury. Adsorbed isoquinoline was observed to go through an abrupt reorientation at potentials more negative than about -0.73 V vs SCE (the actual transition potential being dependent on the bulk solution concentration) to the vertical 6,7 position. 

The SNIFTIRS approach. The acronym SNIFTIRS means Subtractively Normalized Interfacial Fourier Transform Infrared Spectroscopy. The basic concept of this method involves the fact that the raw data obtained directly from the Fourier Transform process contain components which are undesirable. Firstly, there is material in the solution which may have affected the spectrum. Secondly, unwanted information on certain material on the electrode (adsorbed water, for example) is best eliminated. 

Most earlier papers dealt with the mercury electrode because of its unique and convenient features, such as surface cleanness, smoothness, isotropic surface properties, and wide range of ideal polarizability. These properties are gener y uncharacteristic of solid metal electrodes, so the results of the sohd met electrolyte interface studies are not as explicit as they are for mercury and are often more controversial. This has been shown by Bockris and Jeng, who studied adsorption of 19 different organic compounds on polycrystaUine platinum electrodes in 0.0 IM HCl solution using a radiotracer method, eUipsometry, and Fourier Transform Infrared Spectroscopy. The authors have determined and discussed adsorption isotherms and the kinetics of adsorption of the studied compounds. Their results were later critically reviewed by Wieckowski. ... 

Tejedor-Tejedor, M.L Yost, E.C. Anderson, M.C. (1990a) Characterization of benzoic acid and phenolic complexes at the goethite/ aqueous solution interface using cylindrical internal reflectance Fourier transform infrared spectroscopy. Part 5 Methodology. Langmuir 6 979-987... 

Arrondo, J.L., Muga, A., Castresana, J., Goni, F.M. (1993). Quantitative studies of the structure of proteins in solution by Fourier-transform infrared spectroscopy. Prog. Biophys. Molec. Biol., 59, 23-56. 

Poly(vinyl acetate). The dielectric and mechanical spectra of hybrids produced by mixing a poly (vinyl acetate)—THF solution with TEOS, followed by the addition of HC1 have been investigated (45). Mixtures were made which were believed to be 0, 5, 10,15, and 20 wt °/o Si02, respectively. These composites were transparent and Fourier transform infrared spectroscopy (ftir) revealed hydrogen bonding between the silicate network and carbonyl units of the poly(vinyl acetate) (PVAc). No shift in the T of the composites from that of the pure PVAc was observed. Similady, the activation... 

Structural study of polysaccharides and other carbohydrates in solution or in the amorphous state has been significantly enhanced through the application of Fourier-transform, infrared spectroscopy. Among the advantages of this method may be mentioned the high quality of the spectra, and the in-house ability to interact with the computer, so that the digitized spectra may be stored and manipulated in such a way that additional information is obtained. The application of F.t.-i.r. spectroscopy in the field of carbohydrate chemistry and biochemistry is still in its infancy,182 but... 

Fourier Transform Infrared Spectroscopy (FT-IR) measurements were made using a Nicolet Instruments 740 FT-IR spectrometer. A horizontal attenuated toted reflectance cell equipped with a 45° zinc-selenide crystal trough wets used. Spectra of neat solutions were obtained by co-addition of 256 scans at 4 cm- resolution. 

Of the dozen or so methods that have been used to examine the adsorption of biomolecules onto metals from solution, those most suited seem to be (1) cyclic voltrammetry, (2) ellipsometry, (3) Fourier transform infrared spectroscopy, and (4) atomic force microscopy. 

Durrani, C.M., Prystupa, D.A., Donald, A.M., and Clark, A.H. (1993). Phase diagram of mixtures of polymers in aqueous solution using Fourier transform infrared spectroscopy. Macromolecules, 26, 981-987. 

This work was supported by a grant from the National Science Foundation, t Abbreviations used are as follows. FTIR Fourier transform infrared spectroscopy, ATR attenuated total reflectance, IRE internal reflection element, SATR solution ATR FTIR, FSD Fourier self-deconvolution, PLS partial least-squares analysis, PRESS prediction residual sum of squares from PLS. SECV standard error of calibration values from PLS, PLSl PLS analysis in which each component is predicted independently, PLS2 PLS analysis in which all components are predicted simultaneously. 

Altered surfaces have been inferred from solution chemistry measurements (e.g., Chou and Wollast, 1984, 1985) and from spectroscopic measurements of altered surfaces, using such techniques as secondary ion mass spectrometry (for altered layers that are several tens of nm thick (e.g., Schweda et al, 1997), Auger electron spectroscopy (layers <10 nm thick (e.g., Hochella, 1988), XPS (layers <10 nm thick (e.g., Hochella, 1988 Muir et al, 1990), transmission electron microscopy (TEM, e.g., Casey et al, 1989b), Raman spectroscopy (e.g.. Gout et al, 1997), Fourier transform infrared spectroscopy (e.g., Hamilton et al, 2001), in situ high-resolution X-ray reflectivity (Farquhar et al, 1999b Fenter et al, 2003), nuclear magnetic resonance (Tsomaia et al, 2003), and other spectroscopies (e.g., Hellmann et al, 1997). 

Holmen B. A., Tejedor-Tejedor M. I., and Casey W. H. (1997) Hydroxamate complexes in solution and at the goethite-water interface a cylindrical internal reflection Fourier transform infrared spectroscopy study. Langmuir 13, 2197-2206. 

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