Search Results
You are looking at 1 - 10 of 38 items for
- Author or Editor: H. Sato x
- Refine by Access: All Content x
Abstract
Unusually broad119Sn-Mössbauer absorption was observed in pure Sn(CH3)4 or Sn(CH3)4/argon condensed at low temperatures by pulsed deposition. Such broadening of the Mössbauer linewidth suggested the presence of large quadrupole splitting due to possible distortion of molecular structure as deposited in the argon matrix.
Abstract
The structure of chlorotrimethylstannane was studied by Mössbauer spectroscopy in solids, frozen solution, and argon matrices at low temperatures. In frozen solutions, quadrupole splitting was very similar to the value in solid phase, and strong intermolecular interaction may exist between Sn/CH3/3Cl and solvent molecules. In argon matrices, the quadrupole splitting of Sn/CH3/3Cl was much smaller. Comparison of the observed quadrupole splitting with the predicted value based on the point charge model suggests that the Sn/CH3/3Cl molecule may have a tetrahedral structure and be isolated well from each other in the argon matrix.
Abstract
Emission Mössbauer spectra of mixedvalence trinuclear complexes,57Co-labelled [CoFe2O(CH3CO2)6(H2O)3] and [CoFe2O(CH3CO2)6 (py)3]py were compared with that of [CoCr2O(CH3CO2)6 (py)3]py. It was found that the57Fe atoms produced in57Co-labelled [CoFe2O(CH3CO2)6(H2O)3] and [CoFe2O(CH3CO2)6 (py)3]py showed a temperature-dependent mixed-valence state as observed in the absorption Mössbauer spectra of [Fe3O(CH3CO2)6 (H2O)3] and [Fe3O(CH3CO2)6 (py)3]py, respectively, while57Co-labelled [CoCr2O(CH3CO2)6 (py)3]py showed a temperature-independent divalent iron/II/ state. The results indicate that the decayed atoms keep their position at the sites of original57Co atoms and that the valence electrons are transferred through the intramolcular bondings.
Abstract
Photolytic products of tetramethylstannane in low temperature argon matrix were studied by Mössbauer, IR, and UV spectroscopy. At an early stage of the reaction, an unstable tin compound possibly with a tin-carbon double bond was formed in low temperature argon matrix, which might not exist in ordinary conditions. In subsequent reaction, cyclic tin compounds with large quadrupole splittings might be produced.
Abstract
Radiation effects on the extraction of americium(III) with several dialkylphosphoric and monoalkylphosphoric acids have been studied comparatively. The extractants were exposed to60Co γ-rays in the absence and presence of diluent and HNO3. The Df of Am(III) was measured and the yield of radiolytic products was determined after γ-irradiation as a function of the absorbed dose. Di(hexoxyethyl)phosphoric acid was the most susceptible to radiation among the extractants studied and its extractability was weakened by radiation regardless of the presence or absence of diluent or HNO3. Diisodecylphosphoric acid itself showed an enhancement upon irradiation but incurred a depressant effect upon intimate contact with HNO3·Mono(2-ethylhexyl)phosphoric acid showed a decrease of the Df of Am(III), similarly to DIDPA in the presence of HNO3 during γ-irradiation. All the above extractants gave H3PO4 as the principal radiolytic product upon γ-irradiation upon intimate contact with HNO3 causing decreasing solely the extraction of Am(III). Di(2-ethylhexyl)phosphoric acid proved to be the most stable extractant to radiation among those studied.
Abstract
Radiochemical techniques have been applied in various ways to the study of fullerenes and metallofullerenes for the past several years, and they have provided invaluable information pertaining to the stability, structures, and formation of the novel carbon material. This paper reviews those experimental results that have fully shown the usefulness and uniqueness of radionuclides demonstrated in the field of fullerene science.
Abstract
A novel nitrido technetium complex was synthesized by the reaction of the KYCAR (lysyl-tyrosyl-cystyl-alanyl-arginine) ligand with [(n-C4H9)4N][99TcNCl4]. The structure of the complex was analyzed by 1H- and 13C-NMR and IR spectroscopy as well as by elemental analysis. The nitrido technetium complex with KYCAR has a square pyramidal structure in which two KYCARs coordinate to the Tc atom through both an N and a deprotonated S atom of cysteine. The complex possesses a trans configuration.
Abstract
The state of dispersion and photochemical behaviour of tris/
-diketonato/ iron/III/ complexes isolated in low temperature matrices were characterized by means of57Fe Mössbauer spectroscopy. Tris/acetylacetonato/iron/III/ iron/III/ molecules isolated in a nitrogen matrix were aggregated by photoexcitation. Photoreduction of tris/hexafluoroacetylacetonato/-iron/III/ in solid ethanol was also monitored by the Mössbauer technique.
Abstract
The UV photolysis of pentacarbonyliron isolated in low temperature nitrogen matrix was studied by the Mössbauer Technique. Besides stable compounds /Fe2/CO/9 and Fe3/CO/12/ unstable species such as Fe/Co/4 and Fe2/CO/8 were produced by UV irradiation. Furthermore, the unstable species were found to react with nitrogen matrix, leading to the formation of Fe/CO/4N2. Mössbauer parameters of the products were obtained.
