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Showing 1 to 12 of 12 for “"isomer shift"”.
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The Mössbauer effect in surface studies Fe57 on Ag
… square velocity (MOssbauer second-order Doppler shift) of atoms in one and three-dimensional crystals with free surfaces are treated in a many-body approach The simple models indicate that at high temperatures surface atom mean square displacements are on the order of twice bulk atom mean square …
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The Mossbauer effect of FE57 on the surface of tungsten
… above the top layer of the host lattice. The isomer shift with respect to iron at 300 0K is .0151 + .0002 cm/sec in the bulk, and ,018 ± .002 cm/sec on the surface. The temperature dependence of the shift was not determined with sufficient accuracy to detect any surface effects on the .second …
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High pressure Mössbauer studies of magnetic interactions in palladium-cobalt alloys
… somewhere between 4% and 8% Co in Pd. Isomer shift data are also obtained and show a composition independent pressure dependence which is similar to that of Fe57 in Pd, Co, and other close-packed transition metals. This result is briefly related to current theories concerning a pressure …
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The Mossbauer effect in iron under very high pressure
… The center of gravity of o the spectrum shifts with pressure indicating an increase in s electron density at the nucleus. The initial variation, -8 .3 x 10 -5 cm sec -1 kilobar -1 , is consistent with scaling the 4s wavefunction with volume while at higher pressures the variation is …
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High pressure Mössbauer studies on iron and its dilute alloys
Submitted by Carolyn Mead (cmead2@illinois.edu) on 2011-07-08T17:52:37Z No. of bitstreams: 1 1968_moyzis.pdf: 4422269 bytes, checksum: e74d1ab94e5c65293d27be42975e27a0 (MD5)
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Crystal structure, electron density and chemical bonding in inorganic compounds studied by the Electric Field Gradient
… into the nucleus. A correction similar to the isomer shift, coined here the "quadrupole shift" is examined in detail.
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Structural and thermodynamic properties of sodium actinide ternary oxides
… of the neptunium cations were confirmed from the isomer shift values of their Mössbauer spectra. Having established the charge states without ambiguity, XANES spectra were collected at the $Np-L_3$ and $Pu-L_3$ edges to serve as reference data for An(V), An(VI), and An(VII) oxide phases in the …
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[57]Fe Mossbauer studies of surface interactions in a PVD process.
… been confirmed by XRD. Using a model of the 57Fe isomer shift dependence of x, in amorphous alloys yielded x=0.31 +/-0.08 for Fe[x]Ti[1-x] Further experiments using an estimated 25 nm of 57Fe deposited on mild steel without annealing, showed the presence of magnetite and a small quantity of …
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High valent element fluorosulfates and fluoride- fluorosulfates
… was made to extend the linear plot of the isomer shift (6) vs. the quadrupole coupling (SEQ),both of which correlate well with anion basicities, to dimethyltin(IV) carboxylates. To this end, the crystal structures of (CH3)2Sn(OOCR)2 (R = H, CF3 and CH3) were solved. The formate salt, …
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Electronic structure of transition metal ions and clusters
… this ability. Our work suggests that neither the isomer shift nor the quadrupole splitting are strongly influenced by the nature of the coupling between the metal ions, suggesting that broken-symmetry solutions can be used as a basis for computing these parameters in more complex clusters.
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Studies of Some Co-Ordination Compounds of Iron and Cobalt
… 2,2 B.M, however, Mossbauer data showed that the isomershifts corresponded to spin free iron III, thereby indicating that the low moment is due to antiferromagnetic interaction across the Fe - O - Fe bond. A yellow complex possibly a precursor of this oxybridged species has been isolated, Iron III …
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Iron in oxides, silicates and alloys under extreme pressure-temperature conditions
… GPa, and a non-linear behavior of Mössbauer isomer shift for hcp phases of pure Fe and Fe0.9Ni0.1, suggesting an isostructural transition in these phases. We investigate paramagnetic hcp Fe under compression by employing state-of-art calculations (LDA+DMFT) and including many-body correlation …