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Abstract
Some Hungarian zeolites have been studied by Mössbauer spectroscopy. It has been found that Fe3+ ions substitute for Si4+ in tetrahedral position, while Fe2+ ions are chargecompensating cations in octahedral sites.
Abstract
The effect of Xe+ irradiation and that of subsequent annealings on Fe/Sn bilayer have been studied by119Sn conversion electron Mössbauer spectroscopy. It seems that the effectiveness of ion-beam mixing is comparable to the thermal treatment of the bilayer.
Abstract
Iron was diffused into aluminium along grain boundaries and studied by Mössbauer spectroscopy. The Mössbauer spectrum of the investigated sample contained one doublet with isomer shift 
=0.360/5/ mm s–1 /relative to 
-iron/ and quadrupole splitting 
=0.84/l/ mm s–1. These results suggest that the iron atoms in the grain boundaries of aluminium have environment very similar to that which is present in amorphous iron /III/ oxides.
Abstract
Iron injections containing high spin iron(III) complexes may undergo a reductive decomposition during preparation or storage. This process was investigated by the Mössbauer spectroscopy of ice samples prepared by quick-freezing of the injection. The comparison of three model compounds and the correlation between the osmotic pressure of the solutions and their iron(II) concentration formed in the decomposition process and determined by Mössbauer measurements revealed the reason and mechanism of the decomposition.
Abstract
The effect of ion-beam irradiation on the composition and structure of some Co–Sn electrodeposits has been studied by Mössbauer spectroscopy. A transformation of dissolved tin and cubic CoSn to 
-Co3Sn2 was observed.
Abstract
151Sn Mössbauer spectroscopy was performed with tin triflate Sn(OTf)2 in order to determine its Mösbauer parameters for analytical purposes. The typical Mössbauer parameters at 80 K for crystalline Sn(OTf)2 are IS=4.01±0.02 mm/s and QS=1.20±0.04 mm/s and show that the stannous ion is at a site with less than cubic symmetry under perturbation of the crystal field effect.
Abstract
Perovskite type oxides of Ba x Ca1−x Fe0.8Co0.2O3−δ withx=0.95, 0.8, 0.6 and 0.4 have been studied by57Fe transmission Mössbauer spectroscopy. The microenvironment of Fe was found to be sensitively dependent on the Ba to Ca ratio and, more importantly, on the oxygen content. At high Ba concentration, magnetic relaxation is indicated by the Mössbauer spectra. Identification of the various sextets and doublets in the Mössbauer spectra is attempted by the help of thermal treatments of the samples in air and methane as well as by quenching experiments and low temperature measurements.
Abstract
Mössbauer spectroscopy, X-ray diffractometry and microprobe analysis were used to study electrodeposited Fe−Ni−Cr (40–50% Fe, 40–47% Ni, 3–5% Cr) alloys isothermally aged at 500°C from 5 minutes to 100 hours in an inert argon gas atmosphere. The main phase of the as-deposited samples exhibits ferromagnetic microcrystalline behavior, whereas the thermally prepared samples of same composition are always paramagnetic. The dominant effect of ageing is an oxidation process which resulted in the formation of hematite and magnetite iron oxides in considerable amounts and which are attributable to the presence of oxygen inclusions in the as-electrodeposited samples.
Abstract
Eight di-n-butyltin(IV) complexes with glycolic, 2-hydroxy-propionic, succinic and malic acids, have been prepared by two different procedures. The compounds were characterised by elemental analysis, FTIR, Raman and119Sn Mössbauer spectroscopy. The IR and Raman data indicated the presence of bidentate and/or monodentate carboxylate groups, non linear C−Sn−C bonds, and Sn−O bonds within the complexes. The results of Mössbauer spectroscopic measurements, based on point-charge model calculations, have shown the occurrence of trigonal bipyramidal environment in the central tin(IV) atom, besides the octahedral and tetrahedral structure.
Abstract
The implantation of positrons from a22Na source has been studied in two polymer coatings. Transmitted intensities, effective mass absorption coefficients and implantation profiles have been determined.
