Mossbauer spectroscopy single crystal

Sample purity is a key concern. The NRVS experiment is a bulk technique sampling all Fe nuclei, and impurities that also contain the probe nucleus may confound quantitative data interpretation. Impurities may be introduced during sample preparation or may result from sample instability during measurement. Because of this, care must be taken to ensure purity and reproducibility as judged by Mossbauer (see Mdssbauer Spectroscopy), single-crystal X-ray diffraction, electronic absorption spectroscopy (see Electronic Spectroscopy), Raman spectroscopy or other qnalitative techniqnes. 

The isotope is almost exclusively used for the investigation of chemical compounds. The resolving power of Mossbauer spectroscopy is demonstrated by the spectra from WS2 powder and single-crystal measurements as shown in Fig. 7.48 (from [222]). On the right-hand side of the picture, the angular dependence of E2 transitions for Aw = 2, 1,0 hyperfine components is indicated. 

Single-crystal X-ray crystallography remains the only definitive technique for the structural characterization of heteronuclear gold cluster compounds, although other techniques, in particular Mossbauer, NMR, IR, and fast atom bombardment mass spectroscopies (FABMS), have yielded valuable information, especially concerning the nature of these species in solution. Electron spectroscopy, which has proved to be of great value in the identification of homonuclear gold cluster compounds (210) has received little attention by workers in this area,... 

The following sections summarize the applications of fast atom bombardment mass spectrometry, Mossbauer and NMR spectroscopies, and single-crystal X-ray diffraction studies in the characterization of het-eronuclear gold cluster compounds. 

Many complexes that appeared to be An" based on their empirical formulae are really mixed oxidation state Au An complexes. A number of well-characterized examples are given in Table 1. Electron spectroscopy for chemical analysis (ESCA), Au Mossbauer spectroscopy, and single-crystal X-ray structure analyses have been used to distinguish these mixed oxidation state complexes from true Au complexes. The compound AuCb was shown to be a mixed Au -Au tetrameric cyclic complex [AU4CI8] (12) by X-ray structure analysis. 

Local Fe states (using MOssbauer spectroscopy) and thermal expansion coefficient in FeIn2S4 single crystals grown by the directional crystallization of the melt (vertical Bridgman growth) have been studied. 

Hawthorne et al. (1991) used a wide variety of analytical techniques (EMPA, TGA, powder XRD and IR, single crystal XRD, Mossbauer spectroscopy, Si MAS-NMR, EXAFS/XANES spectroscopies and HRTEM) to determine the stmcture of a-decay damaged titanite. The metamictization process was proposed to begin with the formation of isolated defects caused by a-particles and amorphous domains caused by a-recoil tracks which, with increasing dose, overlapped to produce the metamict state. Fe" was reduced to Fe with increasing a-decay dose. In a set of annealing experiments of... 

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