Iron Mossbauer parameters

Bis(imino)pyridine iron complex 5 as a highly efficient catalyst for a hydrogenation reaction was synthesized by Chirik and coworkers in 2004 [27]. Complex 5 looks like a Fe(0) complex, but detailed investigations into the electronic structure of 5 by metrical data, Mossbauer parameters, infrared and NMR spectroscopy, and DFT calculations established the Fe(ll) complex described as 5 in Fig. 2 to be the higher populated species [28]. 

Table 8.3 Mossbauer parameters of iron(II) complexes with intermediate spin (S = 1)...

Table 8.5 Mossbauer parameters of iron(V) and ironfVI) compounds ...

Figure 5.5 The four most common types of Mossbauer spectra observed in iron-containing catalysts along with the corresponding nuclear transitions. Also indicated is how the Mossbauer parameters are derived from the spectra.

Table 5.2 Mossbauer parameters of common iron compounds.

In situ Mossbauer parameters for iron oxides and oxyhydroxides dispersed on high area Schawinigan Black carbon electrode... 

In situ Mossbauer parameters for an iron-nickel mixed oxyhydroxide... 

Contents Basic Physical Concepts. - Hyperfine Interactions. - Experimental. - Mathematical Evaluation of Mossbauer Spectra. - Interpretation of Mossbauer Parameters of Iron Compounds. - Mossbauer-Active Transition Metals Other than Iron. - Some Special Applications. 

Table VI. Mossbauer Parameters of Iron-Silicate Minerals Studied by deCoster, Poliak, and Amelinckx (7, 24) "...

Recently, Evans and co-workers (11) studied the spectra of three orthopyroxenes with Fe/(Mg + Fe) ratios of 0.758, 0.532, and 0.280. They obtained two somewhat asymmetric lines, and their results are summarized in Table VIIIA. One of these authors had previously established by x-ray analysis (12, 13) that the sample with the 0.532 ratio exhibits Mg-Fe ordering, with iron preferring the larger, more distorted M2 site. Consequently it was concluded that the two-line Mossbauer spectra must consist of a superposition of two quadrupole-split doublets nearly coinciding. Mossbauer parameters for iron in these... 

A. Mossbauer parameters for two-line orthopyroxene spectra of varying iron content as determined by Evans, Ghose, and Hafner (11/... 

Present M sbauer Studies of Natural Pyroxenes and Olivines. Table IX gives the major element chemical compositions of the silicate minerals examined in this study. Table X compares the Mossbauer parameters of these minerals, while Figures 9-13 show representative Mossbauer spectra. Fayalite (Figure 9) is the only olivine in this group. The two lines are, however, somewhat broadened (0.35 and 0.39 mm./ sec.) compared with the width of natural iron foil lines observed with our source (0.24 mm./sec.) and suggest the near coincidence of two quadrupole-split doublets resulting from Mi and M2 sites. Analysis of this "two-line spectrum into a four-line spectrum in the manner described by Evans et al (11) could possibly yield parameters for the two iron sites, but this was not undertaken since both lines appear symmetric. The "two-line quadrupole splitting of 2.78 mm./sec. is somewhat smaller... 

Table XI. Mossbauer Parameters of a Synthetic Enstatite-Ferrosilite ( n-Fs) Series as a Function of Iron Concentration Expressed as Percent Ferrosilite Present by Subscript on Fs...

The magnetic properties of deoxyHr indicate that a bridge between the iron centers persists but may be altered from that in oxyHr. The NMR spectrum of deoxyHr exhibits large isotropic shifts for the N-H s on histidines coordinated to the binuclear unit. Mossbauer parameters of deoxyHr (Table II) are typical of high spin iron(II) centers which are at best weakly coupled (37,38,39). Room temperature magnetic susceptibility measurements using the Evans NMR technique... 

Sharrock, M., et al. (1976) Cytochrome P45cam and its complexes. Mossbauer parameters of the heme iron. Biochim. Biophys. Acta 420, 8-26. 

Tab. 7.6 Mossbauer parameters for the iron oxides (RT-data mainly from Murad Johnston, 1987 Murad, 1996 with permission)...

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