Structure of nanosize bimetals Fe-Co and Fe-Ni

The phase composition and structural features of nano-size powders of Fe-Co and Fe-Ni systems synthesized by reducing the metal salts from strongly alkaline aqueous solutions are investigated by XAFS (XANES/EXAFS) and X-ray diffraction methods by using the synchrotron radiation (EXAFS spectrometer and diffractometer of Siberian SR Center) in combination with ordinary X-ray diffraction methods by using DRON-3.0 and Bruker D8 Advance diffractometers.     

Hyperfine magnetic field on Pt in Gd

The hyperfine field on Pt nuclei in Pt-Gd alloys has been studied using the integral perturbed angular correlation technique (IPAC). Results are given for applied fields between 0.2 T and 4 T in the temperature range 13 K to 300 K.     

Hyperfine magnetic field of Zn in iron

Precise hyperfine field value of zinc in iron has been determined by nuclear magnetic resonance on oriented nuclei (NMR/ON): B_hf (ZnFe)=−18.785 (35) T at 7 mK. The relaxation constant of Zn in iron is established C_K=14(3) Ks. The new hyperfine field value of zinc in iron allows a more precise reevaluation of the magnetic moments of^69mZn and^71mZn measured with NMR/ON. and the NICOLE Collaboration, CERN     

Hyperfine structure and nuclear magnetic moments of some neutron-deficient thallium isotopes

Using the atomic-beam magnetic resonance method, hyperfine structure (h.f.s.) measurements have been performed in the²P_1/2 electronic ground state of the neutron-deficient thallium isotopes^193–202Tl. In the doubly odd isotopes, the magnetic dipole hyperfine interaction constantsa were determined, while in the odd-A isotopes, direct measurements of the nuclearg-factors,g _I , were made. The electronicg-factor was measured in¹⁹⁸Tl. The magnetic dipole moments of the doubly odd isotopes have been evaluated by a direct comparison with known values in the stable isotope²⁰³Tl. The moments of the odd-A isotopes are in agreement with pervious measurements by optical spectroscopy. A discussion of the magnetic dipole moments in terms of different nuclear models is included. The moments of the 2^? nuclear ground states of the doubly odd isotopes may be interpreted as arising from a combination of the configurations 2^? (πs_1/2 vf_5/2) and 2^? (πs_1/2 vp_3/2).     

Hyperfine magnetic field on Pd in Pd-Fe alloys

The hyperfine field on Pd nuclei in Pd-Fe alloys has been studied using the integral perturbed angular correlation technique (IPAC). Results are given for samples with iron contents from 3 to 60 at.% Fe and the temperature dependence of the hyperfine field is studied for a sample with 10 at.% Fe.     

Hyperfine fields and magnetic moments in intermetallic ScFe2 with cubic and hexagonal structures

The Sc, Fe and Al NMR spectra have been measured. The spectra and hyperfine fields are dependent on the crystal structures. The magnetic moments of Fe sites were estimated. The magnetic moments of Sc sites μ(Sc) in ScFe₂ (MgCu₂) were evaluated from the magnetic moment per formula μ_∫ as well. μ_∫ in ScFe₂ with hexagonal structures are sharply dependent on the technological conditions and the impurities in the samples.     

Hyperfine field and magnetic moment of V and Cr in iron

The hyperfine fields of ⁵¹V and ⁵³Cr in diluted alloys V_xFe_1?x and Cr_xFe_1?x have been measured by NMR. No concentration dependence is found for x<2%. Therefore we conclude that the magnetic moments of the impurities are constant in contrast to recent neutron scattering results.     

Hyperfine quenching of polarized two-electron ions in an external magnetic field

The hyperfine quenching mechanism of metastable states in polarized heliumlike heavy ions is considered. The lifetime dependence of these states on the ion polarization in an external magnetic field is established. This dependence is presented for the ²³P₀ state of the europium (Z=63) ion and is proposed as a method for the measurement of the ion polarization in experiments for the search of parity violating effects.     

Particle with anomalous moments in an axial magnetic field

The exact solutions of the generalized phenomenological Dirac equation in an axisymmetrical time-invariant magnetic field are discussed. The influence of an anomalous magnetic and a postulated electric moment on the spectrum of fermions moving in that field is investigated.Translated from Izvestiya Vysshikh Uchebnykh Zavedenii, Fizika, No. 5, pp. 36–39, May, 1981.The author is grateful to Prof. V. G. Bagrov for interest and useful consultations.     

The temperature dependence of the57Fe hyperfine magnetic field distribution in Fe-Ni

The temperature dependence of the⁵⁷Fe hyperfine magnetic field (hmf) in Fe-Ni is stronger than the temperature dependence of the⁵⁷Fe hmf in pure Fe. By analyzing the shape of the⁵⁷Fe hmf distribution, and with the help of experiments with Si in Fe-Ni, we deduce that this anomalous temperature dependence originates from a large thermal sensitivity of the magnetic moments at those Fe atoms with more Ni nearest neighbors. A strong temperature dependence of the recoilfree fraction was also observed in Fe-Ni alloys. We suggest that a large mean square thermal displacement of Fe atoms in Fe-Ni is the cause of the anomalous temperature dependence.     

Hyperfine field in Li-Zn-Ti ferrites

The paper reports the⁵⁷Fe Mössbauer effect investigations on the solid solutions of Li_0.5Zn_xTi_xFe_2.5–2xO₄ (x=0 to 0. 6) at 300K. The samples with x0.4 exhibit well defined Zeeman pattern consisting of two sextets corresponding to Fe³⁺ ions at tetrahedral and octahedral sites. The composition with x=0.5 shows a strong ferrimagnetic relaxation whereas the composition with x=0.6 exhibits paramagnetic behaviour. The internal magnetic field at⁵⁷Fe nuclei decreases with increasing x at both the sublattices. This variation is explained in terms of cation distribution and super-exchange interactions. The s-electron density has been observed to be independent of substitution level.     

Measurements of nuclear magnetic moments by transient field techniques

The intense transient magnetic fields have been applied tog-factor measurements of short-lived nuclear states. Significant data for discrete collective high-spin states in¹⁵⁸Dy and in the actinides²³²Th and²³⁸U can be understood by the rotational alignment of valent neutrons and protons, respectively. Measurements on excited states of the self-conjugate nuclei²⁰Ne and²⁴Mg are discussed. The controversial smallg-factor of the²⁰Ne(4⁺) state is particularly exciting since it contradicts all present theories.     

Effect of a magnetic field on the atomic ordering of Fe-Co alloys in nanocrystalline films

The influence of a magnetic field on the process of atomic ordering in films Fe_0.5C_0.5 is studied. It is found that the process of atomic ordering of Fe-Co alloys in nanocrystalline films can be slowed down via the application of magnetic field of relatively low tension (hundreds of Oersted). The effect is due to the influence of magnetic field on diffusion of atoms.     

Magnon instability by a radiation field in magnetic semiconductors and strong d.c. magnetic fields

The magnon damping in an electron-magnon system in the presence of a laser beam and a d.c. magnetic field is discussed. It is shown that near the laser-cyclotron resonance, and for the laser beam propagating perpendicularly to the magnetic field the magnon population in a relatively narrow range of k may grow with time.     

Hyperfine field distributions in ferromagnetic quasicrystals

Recent magnetisation measurements indicated the presence of ferromagnetism in Al−Cu−Mn−Ge quasicrystals with T_c∼535K. In this paper we report the room temperature Mossbauer and X-ray measurements of a series of ferromagnetic AlCuMnFeGe alloys.     

Hyperfine fields and magnetic coupling in Gd metal

New hyperfine field measurements on transition metal impurities in Gd are reported. The data cannot be explained on a simple RKKY model, but are consistent with a mechanism in which magnetic coupling is through the d electrons.