INDEX spectroscopic studies

Whereas within the family of the cubic Prussian blue analogs a large number of lattice constants have been determined, little attention has been devoted so far to polymeric cyanides not belonging to the cubic system. It must be emphasized, however, that polynuclear cyanides having unit cell symmetries other than cubic are by no means rare exceptions. Hexacyanometalates(III) of Zn2+ and Cd2+ are obtained not only in a cubic modification but also as samples with complicated and not yet resolved X-ray patterns of definitely lower symmetry than cubic (55). The exact conditions for obtaining either modification are not yet known in detail. The hexacyanoferrates(II), -ruthenates(II), and -osmates(II) of Mn2+ and several modifications of the corresponding Co 2+ salts show very complicated X-ray powder patterns which cannot be indexed in the cubic system (55). Preliminary spectroscopic studies show the presence of nearly octahedral M C6-units in these compounds, too. 

The present author s researches, dealing with equilibrium measurements in non-aqueous solutions and with various (primarily Mossbauer) spectroscopic studies, required in every case the use of meticulously dehydrated and purified solvents. An account is given below of the methods that proved satisfactory for the purification of some of the more important solvents, with reference to any disturbing factors. For the individual solvents, the boiling point (b.p.), melting point (m.p.) and refractive index n y) at temperature t are given, where appropriate. 

Behrens RL, Wieckowski A (2009) Electrochtarrical and spectroscopic studies of small organic molecule oxidation on low index platinum electrodes. Central Regional Meeting of the American Chemical Society, Cleveland, OH... 

A UV-visible spectroscopic study of 3 and related substances revealed a strong solvatochromic effect, which served as the basis of the establishment of a solvent polarity scale (Buncel and Rajagopal, 1989, 1990,1991). The theoretical study of Rauhut et al. (1993) was based on AMI methodology (Dewar and Storch, 1985,1989) but used a double electrostatic reaction field in a cavity, dependent on both the relative permittivity and the refractive index. Nuclear motions interact with the medium through the relative permittivity, but electronic motions are too fast only the extreme high-frequency part of the dielectric constant is relevant. These authors were able to evaluate solvent-specific dispersion contributions to the solvation energy. The calculations reproduced satisfactorily the experimental solvatochromic results for 3 in 29 different solvents. The method has also been successfully applied to other solvatochromic dyes, including Reichardt s .j,(30) betaine. 

In the wine industry, FTIR has become a useful technique for rapid analysis of industrial-grade glycerol adulteration, polymeric mannose, organic acids, and varietal authenticity. Urbano Cuadrado et al. (2005) studied the applicability of spectroscopic techniques in the near- and mid-infrared frequencies to determine multiple wine parameters alcoholic degree, volumic mass, total acidity, total polyphenol index, glycerol, and total sulfur dioxide in a much more efficient approach than standard and reference methods in terms of time, reagent, and operation errors. 

As a summary of several studies for light elements in unevolved cluster stars (based on photometric or low dispersion spectroscopic indexes), the right panel of Fig. 1 nicely shows the main features. There are star-to star abundance variations, with large spreads in N anticorrelated with much smaller spreads in C (as found all the way from MS to RGB). The implications are that we are not looking simply at a conversion of C into N, and that primordial inhomogeneities... 

A comparison of porphyrin and pincer activity rationalized through reactivity index Porphyrin and pincer complexes are both important categories of compounds in biological and catalytic systems. Structure, spectroscopy, and reactivity properties of porphyrin pincers are systematically studied for selection of divalent metal ions. It is reported that the porphyrin pincers are structurally and spectroscopically different from their precursors and are more reactive in electrophilic and nucleophilic reactions. These results are implicative in chemical modification of hemoproteins and understanding the chemical reactivity in heme-containing and other biologically important complexes and cofactors [45]. 

The studies of Tallin and Buehler indicate that microparticle spectroscopic techniques can be used to follow gas/microparticle chemical reactions. The use of morphological resonances to determine the refractive index of a reacting droplet has limited applicability because there must be a unique relationship between composition and refractive index to allow the method to be used to follow chemical reactions. Raman spectroscopy has broader applications, but one must deal with morphological resonances if droplets are... 

When Barriol begun with his laboratory, he inherited what had been left from the ancient laboratory of Donzelot, the laboratory of physical chemistry. [12] But because the laboratories were poorly equipped in this after-war time, the spectroscopic equipment had already been taken by other laboratories. There remained little at the laboratory of physical chemistry, only something such as a spiritual inheritance and a tradition that wanted to found theoretical speculations on experiment. Two topics were further pursued Raman spectrography, or, more generally, the studies of vibrations inside the molecule, and dielectric problems. The first assistants had to build their own installation for the measurement of dipolar moments, and a part of an installation for the measurement of the refractive index in order to determine the atomic polarization. 

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