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Electronic structures of Cen+1Co3n+5B2n compounds with n=0, 1, 2, and ∞ have been calculated and the magnetic moments of Co and Ce atoms at the respective crystallographic sites have been determined. General features of local density of states for Co atoms in Cen+1Co3n+5B2n are found to be similar to those in Yn+1Co3n+5B2n. It is found that magnetic moments of Ce atoms are not negligible and in opposite direction to the Co-sublattice magnetization in Cen+1Co3n+5B2n with n=0, 1, and 2. The CeCo3B2 compound is found to be nonmagnetic. Calculated magnetic moments in Ce3Co11B4 are in fairly good agreement with neutron diffraction data. Calculated results are also used to explain some experimental data. [ABSTRACT FROM AUTHOR]

The compound Gd5Si4 is known as a candidate for magnetic refrigerant in the vicinity of room temperature. Since Dy ion has a smaller de Gennes factor and larger angular momentum than those of Gd ion, it is expected that the Curie temperature of 335 K and magnetocaloric effect for Gd5Si4 will be decreased and increased, respectively, by Dy substitution for Gd of Gd5Si4. In this study, Gd5-xDyxSi4 with x=0, 0.5, 1, and 2 have been prepared, and the magnetocaloric effects together with the magnetic properties have been measured in a magnetic field up to about 2 T. Maximum temperature rise of 3.1 K is obtained for Gd5Si4 at the Curie temperature of 335 K and in a magnetic field of 1.92 T. The Dy-substituted samples, which have a lower Curie temperature than that of Gd5Si4, have shown almost the same magnetocaloric effect as that of Gd5Si4. The data are discussed on the basis of calculation of magnetic entropy for Gd5Si4. [ABSTRACT FROM AUTHOR]

Magnetic properties of Ce2(Co1-xNix)7B3 compounds with x⩽0.3 have been studied in the temperature region from 4.2 K to 750 K. It is proposed on the basis of experimental data that the compound Ce2Co7B3 has an antiferromagnetic order where the nearest two ferromagnetic layers separated by 12.9 Å couple very weakly antiferromagnetically. Observed metamagnetic transition in Ce2Co7B3 compound is caused by the spin flip. In the compounds Ce2(Co1-xNix)7B3, Ni atoms substitute preferentially the 2c-site Co atoms, and all atoms in the crystals except for the 2c-site Co atoms [=Co(0) atoms] seem to be nonmagnetic. The compound Ce2(Co1-xNix)7B3 becomes Pauli paramagnetic for x larger than about 0.24. [ABSTRACT FROM AUTHOR]

Magnetization measurements for the compound SmCo[sub 3]B[sub 2] have been performed on loose powder in magnetic fields to 5 T and in the temperature region from 4.2 to 60 K. A small saturation moment of 0.18 μ[sub B]/SmCo[sub 3]B[sub 2] at T=4.2 K and its variation with increasing temperature suggest ferrimagnetic ordering in SmCo[sub 3]B[sub 2], which is explained as the effect of a higher order crystalline field coefficient. A magnetic first order transition occurs at T=43 K and metamagnetism occurs in the narrow temperature region between 43 and 47 K, for which some possible discussions are given. © 2000 American Institute of Physics. [ABSTRACT FROM AUTHOR]

Investigates the magnetic properties of rare earth-cobalt-boron compounds. Evaluation of molecular field; Magnetization measurements; Discussion.

Studies the nature of magnetic interactions and chemical bond in Rn+1Co3n+5B2n (R=y and Gd; n=1, 2, 3 and...) compounds. Discussion on the crystallographic regularity of these compound systems; Assessment of the temperature variations of the lattice parameters a and c of the system; Measurement of the Curie temperature by magnetization; Examination of thermal expansion in the paramagnetic temperature region.

Presents neutron diffraction studies on Dy(Cu1-cNix)2Si2 with x = 0, 0.6 and 0.1. Consistency of diffraction patterns with the reported magnetic structure, Neel temperature and the Dy magnetic moment.

Deals with a study which measured the temperature dependence of magnetic susceptibility of RCo[sub3]B[sub2]. Background to the study; Sample preparation and x-ray analysis; Magnetic measurements; Discussion of the results.

Presents a study which examined the role of boron in R[subn+1]cobalt[sub3n+5]boron[sub2n] systems, where R= yttrium, samarium and dysporium and n=0,1,2,3, and ∞. Curie temperature of the samples; Sample preparation and crystal structure; Magnetic measurements and results.

Presents a study which examined the effects of aluminum substitution on the magnetic properties of R cobalt[sub5], where R= ytrrium, praseodymium, neodymium and samarium. Impact of aluminum substitution on cobalt sublattice moments; Methods; Results.

Presents a study that observed magnetic properties of the compound Sm[sub1-x]Pr[subx]Co[sub4-y]Fe[suby]B with various values from the viewpoint of permanent magnet material. Discussion on the possibility of the system for a candidate of permanent magnet material; Crystal structure of the samples; Temperature dependence of spontaneous magnetization of SmCo[sub2]Fe[sub2]B.

Presents a study which investigated magnetic properties of RTiCo[sub11] compounds with the ThMn[sub12] structure. Method used in preparing the compounds; Result of the x-ray diffraction for RTiCo[sub11]; Temperature dependence of the saturation magnetization in RTiCo[sub11] alloys; Description of the x-ray diffraction patterns of YTiCo[sub11].

Presents information on a study which measured the magnetization curves and hysteresis loops of field-oriented powders of rare-earth and related metal compounds. Analysis of the metallic compounds involved in the study; Methodology of the study; Results and discussion.

Presents a study that examined the magnetic properties of yttrium-gadolinium-cobalt-boron. Temperature range by which the compounds have been examined; Structure type of the compounds; Factor that leads to the decrease of the Curie temperature.

Presents a study that measured the magnetization and forced magnetostriction for manganese compounds in the paramagnetic temperature region under a high-pulse magnetic field. Sample preparations; Temperature dependence of magnetizations of the manganese compounds; Diagram of the crystal structure of hexagonal nickel-arsenic type.

Presents a study that investigated the crystal structure parameter of chromium compounds. Temperature dependence of magnetic susceptibility for chromium compounds; Diagram of the crystal structure of the manganese-phosphorus type; Information on the crystallographic parameters of chromium-arsenic.

Presents a study that compared the magnetic properties of several rare earth compounds. Examination of the crystal structure of the compounds; Analysis of the temperature dependence of spontaneous magnetization; Differences in the magnetocrystalline anisotropy of the rare earth-sublattice of the compounds.

Presents a study that investigated the magnetic and crystallographic properties for neodymium cobalt[sub4] boron, aluminum and gallium. Specimens and x-ray analysis; Experimental results and discussion.

Presents a study that examined the effect of aluminum substitution on the magnetic properties of rare earth cobalt[sub5]. Experimental procedures; Results and discussion.

Presents information on a study which analyzed the basic magnetic features for LaCo[sub13]-based systems in which cobalt has been replaced by iron (Fe), aluminum (Al) or Fe and Al and also systems in which lanthanum has been partially replaced by neodymium. Preparation of specimens by an induction melting under a highly pure argon atmosphere; Composition dependence of the magnetic moments of La(Co[sub1-x]Al[subx])[sub13] compounds; Illustration of the qualitative band scheme.

Deals with a study which measured magnetic properties of mixed crystals with NiAs type structure. Background on Curie temperature; Measurement of magnetic moment per manganese atom; Description of magnetic susceptibility.

Examines the magnetic properties of MnAlGe and related compounds. Procedure used in order to find the magnetic properties characteristics of the structure; Susceptibility above the Curie temperature; Measurement of the temperature dependencies of saturation magnetization and electric resistivity.

Presents a study which analyzed magnetocrystalline anisotropy and spin reorientation in Gd[sub1-x]Dy[subx]Co[sub4]B. Information on specimens and crystal structure; Magnetization curves for loose powder; Method used for estimating the magnetocrystalline anisotropy.

Presents a study which examined the magnetization process under a pulsed high magnetic field and the lattice parameters by x-ray diffraction technique on ferromagnet manganese arsenic[sub0.7]antimony[sub0.3]. Sample preparation; Results; Discussion.

Deals with a study which determined the effects of dysprosium substitution on the magnetocrystalline anisotropy of GdCo[sub4]B. Background to the study; Specimens and crystal structure; Experimental results and discussion.

Presents a study which examined the magnetic property of gadolinium cobalt[sub4] boron in high field. Temperature dependence of saturation magnetization and magnetization process of gadolinium cobalt[sub4] boron; Specimens and crystal structures; Experimental results and discussion.

Presents a study that investigated the formation of iron[sub2]-manganese-silicon for Heusler-type L[sub2] structure with some degree of preferential disorder. Information on the sample preparations from iron and manganese; Relation between iron hyperfine field and magnetic moment of iron atom in several alloys; Calculation of iron moments in the various atomic environments.

Presents an abstract of the article 'Magnetic and Crystallographic Properties of R[sub2]Fe[sub14]Si[sub2] (R=Y, Gd, Dy, Er and Tm) compounds,' by K. Konno, H. Ido, F. Pourarian, R.T. Obermyer and S.G. Sanker, which appeared in the 'Journal of Applied Physics.'