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A combination of whole cell transport assays and photoaffinity labeling of Pdr5p were used with [(super 125)I]iodoarylazidoprazosoin in purified plasma membrane vesicles to study the behavior of two series of novel substrates namely trityl (triphenylmethyl) and carbazole derivatives. The result showed that site 2, defined initially by tritymidazole efflux requires at least a single hydrogen bond acceptor group.

The synthesis and structural characterization of novel tetranuclear and octanuclear iron(III) complexes were described. The structures of the iron(III) complexes are based on an almost square arrangement of four iron ions. The tetranuclear iron complex (Fe4(mu-O)2(mu-BMDP)2-(mu-OAc)2)(super 4+) is formed by reacting ferric nitrate, sodium acetate and the unsymmetrical binucleating ligand HBMDP. The tetranuclear iron complex was found to have coordination number asymmetry.

Iron octaethyltetraazaporphyrin (Fe OETAP) complexes were prepared and subjected to spectroscopic, crystallographic, voltammetric and magnetic susceptibility studies. The results showed that Fe(OETAP), porphyrins and phthalocyanines featured similar properties. However, Fe(OETAP) exhibited greater sigma donor and pi acceptor activity than porphyrins and higher dissolution rate than phthalocyanines.

The use of mechanical alloying for the synthesis of Fe-W alloys was investigated using Mossbauer and magnetic susceptibility measurements. The results showed that a six line pattern associated with magnetic ordering appeared during the initial milling process. Continued milling induced a transformation of the spectrum into a broad singlet characteristic of nonmagnetic materials. After 7 hours of the milling process, the iron component of the material homogenized and became amorphous.

New organotin(IV) complexes with empirical formula Sn(SNNNS)R2, where SNNNS is the dianionic form of 2,6-diacetylpyridine Schiff bases of S-methyldithiocarbazate (H2dapsme) or S-benzyldithiocarbazate (H2dapsbz) and R = Ph or Me, have been prepared and characterized by IR, UV-Vis, NMR and Mossbauer spectroscopic techniques and conductance measurements. The molecular structures of the Sn(dapsme)R2 (R = Ph and Me) have been determined by single crystal X-ray diffraction techniques. Both complexes have a distorted pentagonal-bipyramidal geometry in which the tin is coordinated by a dinegatively charged pentadentate chelating agent via pyridine nitrogen, two azomethine nitrogens, and two thiolate sulfurs. The five donors (N3S2) provided by the Schiff base occupy the equatorial plane close to a pentagonal planar array while the carbanion ligands occupy axial sites. [ABSTRACT FROM AUTHOR]

This document is a compilation of ground-breaking papers published in the journal Applied Spectroscopy. It includes a selection of papers that cover a wide range of topics and have been recognized with awards and citations. The papers discuss various techniques and advancements in spectroscopy, such as optimizing instrumental parameters, variable temperature sample holders, depolarization ratio measurements, and high-pressure spectroscopy. Additionally, the document contains reviews on various topics related to spectroscopy and analytical chemistry, providing valuable information for researchers and practitioners in the field. Another section of the document contains summaries of various articles related to spectroscopy, covering topics such as the analysis of near-infrared spectra, the measurement of optical and dielectric constants, and the development of Fourier transform Raman spectroscopy. These articles provide valuable insights into the techniques and applications of spectroscopy in different fields. Lastly, the document contains summaries of several scientific articles related to spectroscopy, covering topics such as 2D correlation spectra, surface-enhanced infrared spectroscopy, and subsurface probing using spatially offset Raman spectroscopy. Each summary provides a brief overview of the article's content and findings. [Extracted from the article]

We have previously reported the stability of europium oxalate compared to ammonium europium bis-salen and europium benzoate. We now extend the dicoarboxylic acid chain of the oxalate by introducing additional-CH2-groups in the dicarboxylate ligands by using malonate, succinate, glutarate and adipate. Additionally, we have examined the effect of alterations in the succinate dianion by introducing functional groups such as [C = C]in the case of the maleide and-OH group in the case of the malide. This study is an attempt to further characterize these compounds. Infrared spectra were used to characterize bridging and chelating dicarboxylates while Mössbauer spectroscopy measurements were used to gain better insight into the structure of heterocyclic “cages” containing two Eu3 + ions and two dianions. [ABSTRACT FROM AUTHOR]

The use of Mössbauer spectroscopy to investigate nanoparticle systems is fairly widespread. In this study, nanoparticles of a europium salen complex, NH4 Eu (salen)2, were prepared by the sol–gel method, and its properties investigated using infrared and Mössbauer spectroscopy. The size of the nanoparticles was measured using an atomic force microscope. The Debye temperature of the nanoparticles was determined from the Mössbauer spectrum and compared with the Debye temperature of the salen complex previously reported. The infrared spectral data support the Mössbauer spectroscopic results. [ABSTRACT FROM AUTHOR]

The speciation of several tributyltin and triphenyltin compounds under varying salinity conditions (0, 20, 40 and 60%) was studied by Mössbauer spectroscopy in both anaerobic and aerobic Anacostia River sediments. The Mössbauer spectral parameters of the spiked sediments indicated that changes in the salinity did not affect the speciation of the tin compounds in either aerobic or anaerobic sediments. [ABSTRACT FROM AUTHOR]

The effects of pH on the speciation of some tributyltin and triphenyltin compounds in spiked sediments from the Anacostia River were studied. The compounds included tributyltin chloride, oxide, and acetate as well as triphenyltin chloride, hydroxide, and acetate. Mössbauer spectroscopy was used to measure the speciation of the triorganotin compounds in the spiked sediments. In general, for the three pHs (5, 7, and 9) studied, the Mössbauer parameters, quadrupole splitting, and isomer shift, varied depending upon the sediment site and the pH. The ? -values (ratio of quadrupole splitting to isomer shift), which indicate the co-ordination of the tin atom, were greater than 2.1 in all cases, indicating that the co-ordination around the tin atoms in all the spiked sediments is greater than four. The variation in the Mössbauer parameters with pH at different sites in the Anacostia River reflects the variation in the components of the sediments. [ABSTRACT FROM AUTHOR]

Complexes of cytochrome c and of an undecapeptide of the protein have been studied by means of Mössbauer spectroscopy in order to obtain information concerning the active heme site. The variation &the quadrupole splitting with the temperature pewits an evaluation of the distortions from octahedral symmetry around the iron ion in the heme group, and also an estimation of the spin-orbit constant. The effect of the different ligands such as CN-, F-, imidazol, etc., is discussed. [ABSTRACT FROM AUTHOR]