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Amorphous thin films of DyFe and DyFeCoy, with various x and y values and of ~40 nm thickness, have been prepared by sputtering on polyimide films. Their magnetization curves and the Mssbauer spectra indicate that at 295 K the iron moments are preferentially oriented parallel to the film in DyFe and that DyFe is paramagnetic. The DyFe thin films, where x is 17, 20, 24, 29, 32, 35, and 37, show perpendicular magnetic anisotropies and moderate coercive fields of at most 150 kA/m, whereas the DyFesCo thin films, wherey is 8, 13, 16, and 20, thin films show stronger perpendicular anisotropies and larger coercive fields of ~400 kA/m. The introduction of cobalt into the amorphous thin films increases their coercive field and the perpendicular magnetic anisotropy. The Mssbauer spectra of the DyFe and DyFeCo amorphous thin films consist of broadened sextets which have been analyzed with a distribution of hyperfine fields by assuming that the iron moments are oriented perpendicular to the plane of the film. Detailed fits of the Mssbauer spectrum of DyFe indicate that the cone angle of the iron magnetic moments cannot be determined with accuracy. The average hyperfine fields in the DyFe amorphous thin films are smaller than those in the crystalline dysprosium--iron intermetallic compounds. The average hyperfine field increases from ~140 kOe in the DyFe films to ~220 kOe in the DyFeCo films, an increase which is in agreement with the increase in the saturation magnetization. The x dependence of the isomer shift indicates that there is strong dysprosium--iron bonding, whereas the y dependence of the isomer shift reveals an enhancement of the d-electron localization. From earlier x-ray magnetic circular dichroism results and the Mssbauer spectral resu... [ABSTRACT FROM AUTHOR]

Presents information on the measurement of the 295 K neutron diffraction patterns and the temperature dependence of the Mossbauer spectra of neodymium (Nd)2 iron (Fe)17-x titanium (Ti) and Nd2Fe17-xTi nitrogen (N). What the insertion of the interstitial nitrogen into Nd2Fe16.32Ti0.68 produces; Information on the observed magnetic hyperfine fields.

Presents a study on the magnetic properties of a series of Nd[sub2]Fe[sub17-x]Al[subx] solid solutions using magnetic measurements, neutron diffraction, and Mossbauer spectroscopy. Experimental methods; Details of the magnetic measurements; Characteristics of the Mossbauer spectroscopy; Results.

Presents information on a study of the structure and magnetic properties of Y[sub2]Fe[sub14-x]Si[subx]B solid solutions. Results of neutron diffraction; Results of Mössbauer spectra; Basis for the silicon affinity for a transition metal site with rare earth near neighbors.

Presents a Mossbauer spectral study of neodymium[sub2]iron[sub15]gallium[sub2] and the terbium[sub2]iron[sub17-x]gallium solid solutions. Methodology; Results; Discussion.

Presents and analyzes the Mössbauer effect spectra of Th[sub2]Fe[sub17] and Th[sub2]Fe[sub17]N[sub2.6] with a model which is both consistent with that used for R[sub2]Fe[sub17] and R[sub2]Fe[sub17]N[sub2.6] spectra and with neutron-diffraction results. Isomer shifts for each sextet assigned to a specific crystallographic site; Application of Wigner-Seitz cell analysis; Effect of nitrogenation on the isomer shifts of different iron sites in Th[sub2]Fe[sub17].

Presents a neutron-diffraction and Mössbauer effect study of the preferential silicon site occupation and magnetic structure of Nd[sub2]Fe[sub14-x]Si[subx]B. Procedures for the preparation of the samples; Analysis of the neutron-diffraction patterns; Contour plot of the number and length of iron-iron bonds.

Deals with a study which measured the magnetic properties of Pr[sub2]Fe[sub17] and Pr[sub2]Fe[sub17]N[sub2.6]. Description of structural changes; Comparison with the Mössbauer spectra of Nd[sub2]Fe[sub17] and Nd[sub2]Fe[sub17]N[sub2.6]; Indication of temperature dependence of isomer shifts.

Presents information on a study which examined the role of Mössbauer spectroscopy in understanding the effect of the interstitial nitrogen on permanent magnet materials. Background of the study; Methodology of the study; Results and discussion.

Examines the measurement of the mossbauer spectra of Nd6Fe13X. Analysis of the spectra in terms of two basic models; Investigation of the magnetic properties of the Nd6Fe13X compounds; Similarity between the spectra of Nd6Fe13Ag and Nd6Fe13Cu.

Focuses on a study which examined the magnetic properties of a series of Ce[sub2]Fe[sub17-x]Al[subx] solid solutions through magnetic measurements, neutron diffraction, and Mossbauer spectroscopy. Experimental methods; Results; Discussion.

Presents information on a study which analyzed the magnetic properties of a series of Ce[sub2]Fe[sub17-x]Si[subx] solid solutions. Experimental methods; Discussion of the Mössbauer spectra; Results and discussion.

Presents information on a magnetic and Mssbauer spectral study of mixed valent lanthanum-strontium-copper-iron-oxide perovskites. Ratio of iron(III) and iron(IV) of mixed valent compounds; Experimental details; Results.

Studies the influence of the insertion of hydrogen or deuterium upon the structural magnetic properties of the radon-iron rare-earth compounds. Experimental procedure; Structural and magnetic properties of praseodymium-iron-hydrogen compounds.

Studies the electric properties of Ce2Fe16.8 and the Ce2Fe17-xAlx and Ce2Fe17-xSix solid solutions. Temperature dependence of the electrical resistivity of Ce2Fe16.8; Temperature dependence of the magnetization of Ce2Fe16.8.

Presents a study which measured the M&oumi;ssbauer effect spectra of praseodymium[sub2]iron[sub17]deuteride. Experimental methods; Presence of a spin reorientation of the iron magnetic moments; Temperature dependence of the isomer shifts.

Focuses on a study which examined the magnetic properties of a series of Tb[sub2]Fe[sub17-x]Al[subx] solid solutions by neutron diffraction and Mössbauer spectroscopy. Background on the materials; Description of the experimental setup; Findings.

Presents information on a study that measured the Mössbauer spectra of Sm[sub2]Fe[sub17] and Ho[sub2]Fe[sub17] and their nitrides. Experimental procedure; Results and discussion.

Provides information on a study which examined systematic neutron diffraction and Mössbauer effect of rhombohedral neodymium compound containing various amounts of aluminum. Methods; Results; Discussion.

Presents a study which examined the changes in magnetic and crystallographic properties in the series Th[sub2]Fe[sub17]C[subx] compunds. Method used in producing the compounds; Measurement of the temperature dependence of the magnetization; Overview of the Mössbauer spectra of the Th[sub2]Fe[sub17] and its ternary nitride.

Presents information on a study which examined the neutron diffraction and Mössbauer effect on the magnetic structure of a metallic compound. Description of the metallic compound; Methodology of the study; Results and discussion.

Presents a study that measured the [sup57]iron Mössbauer-effect spectra of the series of hard magnetic materials, R[sub2]iron[sub14]carbon. Value of R; Exhibition of uniaxial magnetic anisotropy in the carbides; Characteristics of the spectra.

Presents a study which investigated neutron diffraction and Mössbauer effect of praseodymium[sub2](iron[sub1-x]manganese[subx])[sub14]boride. Sample preparation; Analysis of the Mössbauer spectrum; Results of the neutron diffraction analysis.

Presents a study which examined a series of Y[sub2](Fe[sub0.6]Mn[sub0.4])[sub14]B by using Mössbauer spectrescopy and neutron diffraction. Materials and methods used; Results of the study; Discussion.

Presents a study which measured the Mössbauer spectra of Y[sub2]Fe[sub14]B. Materials and methods used; Details on the M&oumlssbauer spectral analysis; Description of the Mössbauer spectra and fits of Y[sub2]Fe[sub14]B as a function of temperature; Overview of the Mössbauer spectra and fits for Y[sub2](Fe[sub1-x]Al[subx])[sub14]B.

Presents a Mossbauer spectra study of the magnetic properties of terbium and iron (Tb2Fe17) and the Tb2Fe17-xSix solid solutions. How these solutions were prepared for this study; Information on the magnetization of the Tb2Fe17 compound; Differences that were observed in the shape of the spectra with various temperatures; Results of this study.

Presents a study which examined samples of Nd[sub2]Fe[sub16]TiC with the Th[sub2]Zn[sub17]-type rhombohedral structure using powder x-ray and neutron diffraction, magnetic measurements, and Mossbauer spectroscopy. Description of the neutron diffraction determined titanium site occupancies; Reason for the differences in the occupancies; Description of the Mössbauer spectra of the Nd[sub2]Fe[sub16]Ti.

Presents an abstract of the paper `An X-Ray Absorption Spectral Study of the Ce2Fe17-xMx Solid Solutions, Where M Is Aluminum or Silicon,' presented by D. Vandormael, F. Grandjean, et al, at the American Institute of Physics' 1997 Conference on Magnetism and Magnetic Materials.

The magnetic, electronic, and Mössbauer spectral properties of [Fe(2)L(μ-OAc)(2)]ClO(4), 1, where L is the dianion of the tetraimino-diphenolate macrocyclic ligand, H(2)L, indicate that 1 is a class III mixed valence iron(II∕III) complex with an electron that is fully delocalized between two crystallographically inequivalent iron sites to yield a [Fe(2)](V) cationic configuration with a S(t) = 9∕2 ground state. Fits of the dc magnetic susceptibility between 2 and 300 K and of the isofield variable-temperature magnetization of 1 yield an isotropic magnetic exchange parameter, J, of -32(2) cm(-1) for an electron transfer parameter, B, of 950 cm(-1), a zero-field uniaxial D(9∕2) parameter of -0.9(1) cm(-1), and g = 1.95(5). In agreement with the presence of uniaxial magnetic anisotropy, ac susceptibility measurements reveal that 1 is a single-molecule magnet at low temperature with a single molecule magnetic effective relaxation barrier, U(eff), of 9.8 cm(-1). At 5.25 K the Mössbauer spectra of 1 exhibit two spectral components, assigned to the two crystallographically inequivalent iron sites with a static effective hyperfine field; as the temperature increases from 7 to 310 K, the spectra exhibit increasingly rapid relaxation of the hyperfine field on the iron-57 Larmor precession time of 5 × 10(-8) s. A fit of the temperature dependence of the average effective hyperfine field yields |D(9∕2)| = 0.9 cm(-1). An Arrhenius plot of the logarithm of the relaxation frequency between 5 and 85 K yields a relaxation barrier of 17 cm(-1).