Mdssbauer spectrum

In spite of careful analysis of the products with the various sophisticated probes, differences in the composition are reported. All measurements indicate a zinc-deficient zinc ferrite, but the indicated zinc concentration varies from 0.2 to 0.9. The EDS measurements are based on direct zinc concentration measurements. Determinations based on magnetization and Mdssbauer spectra are obtained on zinc ferrite synthesized in more conventional processes. 

I2H2O as a function of the reciprocal temperature. The points are data obtained from fits of the Mdssbauer spectra (Fig. 6.6). The broken curve is a fit to the Einstein model for a Raman process. The dotted curve corresponds to a contribution from a direct process due to interactions between the electronic spins and low-energy phonons associated with critical fluctuations near the phase transition temperature. (Reprinted with permission from [32] copyright 1979 by the Institute of Physics)... 

Fig. 7.11 Cu( Ni) emission Mdssbauer spectra of (a) CU2O, (b) jjje quadrupole...

Fig. 8.8 Pressure dependence of the Fe Mdssbauer spectra of [Fe(2-pic)3]Cl2-C2H50H at 121 K. The area fiaction of the LS doublet (inner two lines) increases by application of pressure (from [18])...

Figure 2. Mdssbauer spectra of the FesSa cluster of 13. g/gasFdn. (A) Spectrum of the oxidized cluster (S = 1/2) taken at 100 K. (B) 4.2 K spectrum of the reduced cluster (S = 2) recorded in zero field see also Figure 4.

Figure 8. Mdssbauer spectra of activated aconitase recorded at 4.2 K in zero field (A and B) or in a magnetic field of 60 mT applied parallel to the observed 7-radiation (C). fA) En me activated with <90% enriched pe. (B) En rme activated with Fe in the presence of 10 mM citrate. (C) En me activated with 99.9% enriched Fe in the presence of 10 mM citrate. (Reproduced with permission from ref. 57. Copyright 1983 the authors.)...

Murad, E. Schwertmann, U. (1983) The influence of aluminium substitution and crystallinity on the Mdssbauer spectra of goethite. Clay Min. 18 301-312... 

Very few Mdssbauer spectra of R-dtp complexes have been reported. Fe(III)S6 complexes frequently participate in a high spin-low-spin equilibrium... 

Notwithstanding these studies, the role of the iron cluster in the catalysis remains an enigma. Clearly, the substrate binds to the Fca site by the Mdssbauer spectra. Also, the ENDOR spectra of aconitase with specifically 0-labeled substrates and inhibitors imply that the )3-carboxyl... 

Antitumor drugs cisplatin as, history, 37 175-179 platinum compounds future studies, 37 206-208 resistance to, 37 192-193 second-generation, 37 178 Antiviral agents, 36 37-38 AOR, see Aldehyde oxidoreductase Aphanothece sacrum, ferredoxins, amino acid sequence, 38 225-227 Apo-calcylin, 46 455 Apo-caldodulin, 46 449-450 Apoenzyme, 22 424 Apoferritin biosynthesis, 36 457 cystalline iron core, 36 423 Fe(III)distribution, 36 458-459 Fe(II) sequestration, 36 463-464 ferroxidase centers, 36 457-458 iron core reconstruction in shell, 36 457 mineralization, 36 25 Mdssbauer spectra, 36 459-460 optical absorbance spectra, 36 418-419 subunit conformation and quaternary structure, 36 470-471... 

Mdssbauer spectra of bonding and structure in, 15 184-187 reactions with diborane, 16 213 stabilization of, 5 17, 18-19 cyanates, 17 297, 298 cyanide complexes of, 8 143-144 cyclometallated bipyridine complex, 30 76 diazene complexes, 27 231-232 dinitrogen complexes, 27 215, 217 diphosphine complexes of, 14 208-219 dithiocarbamates, 23 253-254 -1,2-dithiolene complexes, 22 323-327 hydrogen bonding, 22 327 halide complexes with phosphine, etc., 6 25 hexaflouride, structure, 27 104 hydride complexes, 20 235, 248-281, see also Transition metal-hydride complexes... 

Mdssbauer spectra of NaY-encapsulated FePc(t-Bu)4/NaY and external FePc(t-Bu)4+NaY at 78 K are shown in Fig 4. The Mfissbauer paraaeters after curvefitting analysis suggested that the Fe precursor in NaY reacted with 1,2-dicyanobenzene to be converted into iron phthalocyanine derivatives without any other residual species of iron. The appreciable difference was observed for I.S. and Q.S. values between the internal and external sanples of FePc(t-Bu)4, suggesting that the electron density at the central Fe of FePc(t-Bu)4 inside... 

The ideal W structure of BaFeis027 and SrFcigOz contains S blocks twice as thick between each R block to give the stacking sequence RS2R SJ. There are therefore seven non-equivalent iron sites, and Mdssbauer spectra at 5 and 78 K were able to resolve all... 

A similar absolute calibration method uses a diffraction grating on the end of the drive shaft opposite to the y-ray source (30). In either case, however, these methods of absolute velocity calibration provide a determination of the drive shaft motion during collection of all Mdssbauer spectra, and as such offer an important advantage over indirect methods of velocity calibration. 

Figure 6.34. Mdssbauer spectra and their decomposition for Ca2Fc205 activated for 10 min at the absence (a) or presence (b) of water (dots measured spectra).

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