Aggregate Formation in High Dose Iron Implanted MgO Single Crystals Studied by Optical Absorption and Conversion Electron Mössbauer Spectroscopies
0
Citation
8
Reference
10
Related Paper
Keywords:
Superparamagnetism
Mossbauer studies of ultrafine particles of iron are reported. The particles have an average diameter of 2 nm and are dispersed in oil by a surface-active agent. The Mossbauer spectrum at 4.2 K consisted of a ferromagnetic and a paramagnetic component. The paramagnetic component was shown to disappear when the sample was kept at room temperature. It is concluded that particles having diameters less than a certain value are paramagnetic.< >
Component (thermodynamics)
Ultrafine particle
Cite
Citations (5)
Superparamagnetism
Cite
Citations (0)
This book reviews some of the uses of the Mossbauer effect. Topics considered include gamma resonance revisited: temporal aspects of absorption and scattering; relaxation spectra in Mossbauer spectroscopy; dynamics of proteins; metals and alloys: amorphous metals; coherent transients in Mossbauer spectroscopy; the study of radiation phenomena in solids by Mossbauer technique and related methods; Mossbauer emission spectroscopy and after-effects of nuclear transformations; and structure and properties of magnetic alloys.
Cite
Citations (1)
The recently synthesized Au(V) complex fluorides of the form A+ AuF6− with A = Xe2F11+, XeF5+, and Cs+ have been studied by Mössbauer spectroscopy with the 77.3 keV gamma resonance of 197Au. The values obtained for isomer shift and electric quadrupole interaction are in harmony with the assigned oxidation state Au(V), as well as with the octahedral shape of the AuF6− anion.
Quadrupole splitting
Oxidation state
Cite
Citations (26)
Superparamagnetism
Zinc ferrite
Cite
Citations (11)
Mossbauer spectroscopy has been applied to analyse the iron compounds present in car exhausts. From the shapes of the Mossbauer spectra at room temperature it is inferred that iron appears basically as alpha -Fe2O3 in the form of ultra-fine particles, of approximately 120 AA diameter, in the superparamagnetic phase and also in ferromagnetic phase.
Superparamagnetism
Ultrafine particle
Cite
Citations (6)
It has been found in investigating the Mossbauer effect in tin-organic compounds that singlet Mossbauer lines appear in compounds with four identical substituents (SnCl/sub 4/, Sn (C/sub 6/H/sub 5/)/sub 4/) whereas if different substituents (R/sub i/Sn X/sub 4 -i/) are present in the molecule a very strong doublet splitting of the Mossbauer lines occurs (the two peaks sometimes being different in intensity and width). The Mossbauer effect has been observed in amorphous media (tin containing glass) for the first time. Some data are obtained which indicate that the decisive factor determining the shape of the Mossbauer spectra (isomer shift and quadrupole splitting) are the molecular bonds closest to the tin nuclei. (auth)
Quadrupole splitting
Cite
Citations (0)
Superparamagnetism
Solid-state physics
Cite
Citations (3)
High field Mossbauer spectroscopy provides a selective method of measurement of the magnetic susceptibility due to paramagnetic Mossbauer atoms, and is well adapted for isotropic ions. This method was successfully tested on crystalline KFeF4 above its Neel temperature. In the case of MnFeF5(H2O)2, a reversal of the susceptibility of the iron sublattice was observed near 145 K, and explained in agreement with previous data on the magnetic interactions.
Néel temperature
Cite
Citations (4)
We report the temperature and field dependence of dc magnetization on sol-gel prepared nanoparticles of Ni(OH)_2. At higher temperature the system is found to behave as a paramagnet while we find evidence for superparamagnetic blocking at low temperature. The system shows a paramagnet-superparamagnet transition and we discuss the underlying mechanism.
Superparamagnetism
Cite
Citations (0)