Search results for "Knight shift"
showing 10 items of 10 documents
Crystal Field Excitations in CeAgl−xInx Compounds
1982
The substitution of the monovalent Ag for the trivalent In in LaAgl−xInx and CeAgl−xInx offers the possibility of influencing the conduction electron system in these compounds. The strong dependence of the spin susceptibility of La-systems on the In-concentration1 was interpreted by band calculations which suggest that the Fermi level is pushed into a region of a high 5d-eg-band density of states2. Furthermore, CeAgl−xInx is one of the rare 4f systems where a structural phase transition (from cubic to tetragonal) occurs prior to magnetic ordering. The ferromagnetic Curie temperature TC is roughly independent of x whereas the structural transition temperature Ts rises from 15 K for CeAg to a…
Anomalous Muon Knight Shift Behavior in a Cd Single Crystal
1983
For the positive muon implanted in a metal the precession frequency shift due to hyperfine fields can be measured with high precision. This provides means to obtain information about the local electronic structure of a hydrogen like impurity in any metal in the indefinitely dilute impurity concentration. Ref. 1 gives a summary of the muon Knight shift (KS) investigations in 18 nontransition (simple) metals and some transition metals and discusses the results in the context of the electronic structure of hydrogen in metals.
Muon Knight-shift measurements in CeSn3and some isostructural rare-earth compounds
1984
Spherical solid model for muon and hydrogen in metals
1979
The spherical solid model and the spin density functional formalism have been applied to calculate the screening of a positive point charge at different lattice sites in Al, Na and Cu. Results are obtained for the Knight shift, the electric field gradient, the heat of solution and the diffusion barrier. It is found essential to use the spin-polarised form to evaluate the Knight shift, especially at low metallic densities and for impurities with a high nuclear charge. Both the Knight shift and the electric field gradient are found to be markedly different for substitutional and interstitial positions. The calculated heat of solution of hydrogen is lowest for the octahedral position in FCC Al…
Muon knight shift measurements in the alkali and alkaline earth metal series
1979
Anisotropic muon Knight shift in the HCP single crystals of Cd, Zn and Be
1984
In single crystal samples of Zn, Cd and Be (hcp structure) stroboscopicμSR measurements successfully revealed anisotropies in the muon Knight shift (Kμ). An anisotropic Kμ can provide information on the amount of non s-electrons screening the charge of the muon implanted in these metals as a light hydrogen isotope. In Cd, the anisotropic part depends strongly on the temperature and shows a change in sign at roughly 110 K. In Zn, the anisotropic part below 10 K turns out to comprise 4th order contributions in the direction cosines of the external field. This can be understood on the basis of an anisotropicg-factor of the conduction electrons or spin-orbit coupling, respectively.
Muon Knight shift at a structural defect in zinc crystals
1984
The interaction of a light hydrogen isotope with a structural defect is traced for the first time by means of the temperature dependence of the muon Knight shiftKμ in the hcp metal Zn. A surprising result is the huge and negativeKμ (−520 ppm) at the defect site, probably a multivacancy cluster.
Muon states in metals: Recent progress
1984
We report on our results in two interesting questions related to muon spin rotation studies in condensed matter: (i) energetics of muons in metals, including lattice relaxation and zero point motion in self-trapping phenomena, and (ii) systematics of Knight shifts and hyperfine fields.
Muon Knight shift studies in single crystals of Zn and Cd
1981
Recently f i r s t resul ts have been reported on the muon Knight s h i f t in high pu r i t y (6N) spherical s ingle crys ta ls of Cd and Zn [ l ] . These measurements, using a stroboscopic ~SR-technique [2 ] , are extensions of e a r l i e r ~+ Knight s h i f t measurements in nontrans i t ion metals [3 ,4] in which the pos i t i ve muon is used as a "hydrogen" subs t i tu te in the study of i t s local e lec t ron ic s t ructure in a metal environment. Since the s o l u b i l i t y of hydrogen in these metals is general ly very small , no proton-NMR measurements have ever been performed in th is class of metals. To the extent that the mass d i f ference between the proton and the muon is…