Spectra General

Near-IR and visible spectra of the Pu(IV) polymer have been published (27). Although the spectra generally are very broad, the absorptions correspond well to the families of peaks seen for I. Especially notable are features between 1000-1200 nm and 600-700 nm. In each case, the spectrum of I resembles that of... 

Use of Mossbauer spectra generally requires the addition of Fe to the growth medium. This procedure has received extensive application to studying the environment of Fe in enzymes, and illustrative examples include the following ... 

We have seen in Chapter 2 that the frequency of an EPR spectrum is not a choice for the operator (once the spectrometer has been built or bought) as it is determined by the combined fixed dimensions of the resonator, the dewar cooling system, and the sample. Even if standardized sample tubes are used and all the samples have the same dielectric constant (e.g., frozen dilute aqueous solutions of metalloproteins), the frequency will still slightly vary over time over a series of consecutive measurements, due to thermal instabilities of the setup. By consequence, two spectra generally do not have the same frequency value, which means that we have to renormalize before we can compare them. This also applies to difference spectra and to spectra... 

In cases where the substituent on the pyridine ring contains a carbonyl group, a weak band for the C-0 stretch can be detected in the SERS spectra, generally near 1700 cm. ... 

The interpretation of vibrational and electronic spectra of these complexes is much more complicated. Whereas IR spectra generally show only bands of low intensity, tbe Raman spectra often display intense and characteristic lines. Rigorous assignments have not been published so far, but the most simple M(/i2-S), ring systems can easily be... 

A deshielding effect of 15-20 ppm is also observed in the 13C NMR spectra.109 The spectra generally reflect the expected result of replacing a neutral center by apositively charged one. 

Emission spectra General considerations 496 497 5.7. Conclusion on die determination of equilibrium constants by TRES 506... 

Examples of real isomerism of constitution are very numerous we list here a few series of compounds vdiich were more or less easily identified by their XPS valence band spectra. Generally, they are relatively simple polymers in the sense that their monomeric unit contains few atoms for larger systems, it is expected that the distinction between two isomers will be less evident. We distinguish here the two following groups of polymers, and only list the compounds already studied (the list contains all the compounds already studied in the laboratory or elsewhere it is not restrictive all the isomers studied up to now were found different by their valence band spectra) ... 

N NMR spectra—general Book Levy and Lichter B-79MI40900... 

Analysis of the relaxation time indicates that a narrow linewidth in the H NMR spectra generally implies that the protons on the surftice of M-SbA are mobile, while a wide one indicates that proton motion on the surface of M-SbA is rather restricted. The IR spectra study yield absorption bands at 2800-3200 cm to show the presence of free water in addition to the —OH of Sb-OH (2800-3000 cm ). The peaks attributed to the Sb-OH group decrease markedly with increasing uptake of Li. These results indicate that lithium ion exchange is attributed to the dehydration in the M-SbA structure. 

A symmetrical spectral band is described by three parameters position (wavelength or frequency corresponding to the absorption maximum), intensity (absorbance or molar absorptivity at the band maximum) and width (usually the bandwidth at half-height). The band shape functions most commonly used for deconvolution are the Gaussian function and the Lorentzian function. Both are symmetrical functions. UV-visible spectra generally have a Gaussian band shape. The Lorentzian function is useful for the simulation of NMR spectra. The... 

Full-scan mass spectra generally contain an abundant [M - - H] ion signal with little detectable fragmentation. Product-ion spectra are obtained to reveal product ions and neutral losses that are associated with diagnostic substructures of the buspirone molecule. 

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