Mossbauer studies

The same magnetic dependence on temperature was also demonstrated for unsolvated Fe[papt] (694). and a detailed Mossbauer study established that the spin transition is thermally... 

Conversion electron Mossbauer studies of compounds containing iron. F. J. Berry, Transition Met. Chem. (Weinheim, Ger.), 1979,4, 209-218 (60). 

Mossbauer studies on iron proteins. B. H. Huynh andT. A. Kent, Adv. Inorg. Biochem., 1984, 6, 164(178). 

This section on N2 complexes concludes with a brief mention of a Mossbauer study of the Fe/N2 system (8). The N2 stoichiometries were... 

A major discrepancy that remains unresolved in the excited-state properties of the [Fe384]° cluster in D. gigas Fdll concerns the existence of a low-lying, fully valence-delocalized state that becomes populated at temperatures above 25 K. 8uch a state is clearly apparent in the temperature-dependent Mossbauer studies of reduced D. gigas Fdll (29) and P. furiosus 3Fe Fd (198) and is represented by one quad-rupole doublet with AEq 0.9 mm/s and S = 0.45 mm/s. 8uch a... 

Nitrogen coordination of the Rieske cluster had been suggested by Blumberg and Peisach (4) as early as 1974. However, it was only after the pioneering Mossbauer studies of Fee et al. (5) that the coordina-... 

Different metals are readily incorporated into rubredoxin-type centers after reconstitution of apoprotein with appropriate metal salts (5). Rd and Dx derivatives containing Ni and Co have been analyzed by UV-vis, NMR, EPR, electrochemistry, and MCD (13, 19-22). Fe replacement has been used for Mossbauer studies and an indium de-... 

An important advance on these studies was the possibility of isolating AORs from Fe enriched media with obvious interest for an iron-sulfur center site labeling, with enhanced sensitivity of the Mossbauer studies. The work developed with bacterial systems is advantageous as compared with mammalian systems for isotopic labeling and opens the possibility of a direct measurement of substrate binding. Spectra of the enzyme in oxidized, partially reduced, benzaldehyde-reacted, and fully reduced states were recorded at different temperatures and with variable externally applied magnetic fields (222). In the oxidized enzyme, the clusters are diamag-... 

A Mossbauer study of the protein reacted with benzaldehyde (in parallel with EPR detection of Mo(V) signals) shows partial reduction of the iron—sulfur centers, indicating the involvement of the clusters in the process of substrate oxidation and rapid intramolecular electron transfer from the molybdenum to the iron—sulfur sites. 

Another Mossbauer study on molybdenum hydroxylases was performed on a nonenriched sample of milk xanthine oxidase (219), and an unusually large AEq (3.2 mm/s at 175 K) was also observed for the ferrous site of one of the clusters. 

The first In situ MBS Investigation of molecules adsorbed on electrode surfaces was aimed primarily at assessing the feasibility of such measurements In systems of Interest to electrocatalysis (18). Iron phthalocyanlne, FePc, was chosen as a model system because of the availability of previous situ Mossbauer studies and Its Importance as a catalyst for O2 reduction. The results obtained have provided considerable Insight Into some of the factors which control the activity of FePc and perhaps other transition metal macrocycles for O2 reduction. These can be summarized as follows ... 

Shanklin J, C Achim, H Schmidt, BG Fox, E Miinck (1997) Mossbauer studies of alkane w-hydroxylase evidence for a diiron cluster in an integral-membrane enzyme. Proc Natl Acad Sci USA 94 2981-2986. 

Hill, D.T, Sutton, B.M., Isab, A.A., Razi, T, Sadler, P.J., Trooster, J.M. and Calls, G.H.M. (1983) Gold- 197 Mossbauer Studies of Some Gold(I) Thiolates and Their Phosphine Complexes Including Certain Antiarthritic Gold Drugs. Inorganic Chemistry, 22, 2936-2942. 

Belozerskii, G.N. Mossbauer Studies of Surface Layers. Elsevier, Amsterdam (1993)... 

The underlying physics and analysis of Mossbauer spectra have been explained in detail in Chap. 4. In that chapter, the principles of how a spectrum is parameterized in terms of spin-Hamiltonian (SH) parameters and the physical origin of these SH parameters have been clarified. Many Mossbauer studies, mainly for Fe, have been performed and there is a large body of experimental data concerning electric-and magnetic-hyperfine interactions that is accessible through the Mossbauer Effect Database. 

In addition to the examples discussed above, we add the following other reports on Ni Mossbauer studies where only the reference, the material under study, and some remarks about the study are quoted. 

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