The high spin complex Fe(I1) (N, N'-dicyclohexylthiourea)~(C10~)~ exists in two forms which only differ in the distortion from octahedral symmetry of the environment of the Fe ion. Thermodynamic data for the transformation from one form to the other as obtained from Mossbauer spectroscopy are presented and a method to derive kinetic parameters is described.

The preparation of a fluid of cobalt ferrite particles having a size varying from 2 to 5nm is described. This bas been achieved by using functionalized surfactants. The size of cobalt femte particles decreases when the total reactant concentration decreases. The magnetic properties are described with magnetization curves and "Fe mossbauer spectroscopy. It is demonstrated that these particles ar...

Using recoilless Mossbauer spectroscopy methods, we investigate the atomic absorption spectra of the 14.4keV transition in Fe compounds. The natural linewidth of this transition is determined to the correct order of magnitude with χν = .75. Hyperfine energy shifts in iron oxide and iron sulfate are investigated and measured. The ratio of ground and excited state magnetic moment in Fe is found t...

The anaerobic binding of Fe 2+ to apo and holo Mammalian ferritin has been studied in the pH range from 6.0 to 10.0. Mossbauer spectroscopy of samples in which the added Fe 2+ is enriched in Fe-57 shows that the Fe 2+ ions bind to the ferritin core and exchange electrons with Fe 3+ ions in the core.

Both Fe3 + and Fe2 + ions occur in FeCl3-doped polyacetylene. At low dopant levels ( < 0.01 mole frac­ tion) both Fe2 + and Fe3 + io'ns are paramagnetic down to 4.2 K. At dopant levels > 0.01 mole fraction, there is evidence from Mossbauer spectroscopy that Fe2+ ions associate into aggregates which are magneti­ cally ordered below 25 K. Aggregate formation appears to correlate with high electri...

Mossbauer spectroscopy of the synthetic tetramers [Fe4S4(SR)4]2(R = alkyl, aryl) and the corresponding trianions obtained by one-electron reduction, when compared with available data for 4-Fe and 8-Fe iron-sulfur proteins, shows that these tetramers are electronic analogs of the active sites of the proteins.

Two systems of nanoparticles with different surface states have been prepared by sol-gel methods and analysed by X-ray diffractometry, transmission electron microscopy, thermal analysis and temperature dependent Mossbauer spectroscopy. Surface states and phase content, particle mean size and the magnetic anisotropy energy constant were evaluated.

The high spin complex Fe(I1) (N, N'-dicyclohexylthiourea)~(C10~)~ exists in two forms which only differ in the distortion from octahedral symmetry of the environment of the Fe ion. Thermodynamic data for the transformation from one form to the other as obtained from Mossbauer spectroscopy are presented and a method to derive kinetic parameters is described.

We have seen, by Mossbauer spectroscopy, magnetization and resistivity, changes on the physical properties of the aFe20Ni6oB20 alloy induced by thermal relaxation, notedly increases in T, and resistivity. These changes can be explained by modifications of the chemical short range order around Fe favouring the formation of Fe-Ni pairs.

Summarised here are the conclusions of an investigation by differential thermal analysis, magnetic susceptibility, Mossbauer spectroscopy, electrical conductivity and thermoelectric power on single crystal Fe0.996S. There is an increase in conductivity both parallel and perpendicular to the c-axis by a factor 102 at Ta (420 K). At low temperature the I. S. is characteristic of a non-metal but i...