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Magnetic properties, hyperfine interactions, and spin dynamics of rare earth–beryllium intermetallic compounds

1973; Wiley; Volume: 17; Issue: 2 Linguagem: Inglês

10.1002/pssa.2210170230

1521-396X

F. Borsa, G.L. Olcese,

Advanced NMR Techniques and Applications

physica status solidi (a)Volume 17, Issue 2 p. 631-642 Original Paper Magnetic properties, hyperfine interactions, and spin dynamics of rare earth–beryllium intermetallic compounds F. Borsa, F. Borsa Istituto di Fisica dell'Università di Pavia and Gruppo Nazionale di Struttura della Materia del Consiglio Nazionale delle Ricerche, PaviaSearch for more papers by this authorG. Olcese, G. Olcese Istituto di Chimica-Fisica dell'Universita di GenovaSearch for more papers by this author F. Borsa, F. Borsa Istituto di Fisica dell'Università di Pavia and Gruppo Nazionale di Struttura della Materia del Consiglio Nazionale delle Ricerche, PaviaSearch for more papers by this authorG. Olcese, G. Olcese Istituto di Chimica-Fisica dell'Universita di GenovaSearch for more papers by this author First published: 16 June 1973 https://doi.org/10.1002/pssa.2210170230Citations: 36AboutPDF ToolsRequest permissionExport citationAdd to favoritesTrack citation ShareShare Give accessShare full text accessShare full-text accessPlease review our Terms and Conditions of Use and check box below to share full-text version of article.I have read and accept the Wiley Online Library Terms and Conditions of UseShareable LinkUse the link below to share a full-text version of this article with your friends and colleagues. Learn more.Copy URL Share a linkShare onFacebookTwitterLinkedInRedditWechat Abstracten Measurements of lattice parameter, magnetic susceptibility, and 9Be nuclear magnetic resonance and relaxation were performed in a series of rare-earth–beryllium intermetallic compounds REBe13 (RE = La, Cc, Nd, Gd). The anomalous results in CeBe13 can be inter-preted in terms of the presence of variable concentrations of Ce3+ and Ce4+ ions in the sample with a lifetime of the order of 10−13 s. In NdBe13 it is found that crystal field effects are important in the temperature range investigated and they preclude magnetic order down to 1.5°K. GdBe13 becomes ferromagnetic at about 22°K but the magnetic susceptibility is anomalous below about 100°K. Both in NdBe13 and GdBe13 the 9Be asymmetric NMR spectrum at high temperature can be explained by considering only the magnetic dipolar interaction of the nuclei with the paramagnetic moments while the isotropic part of the shift is small and negative. From the 9Be spin–lattice relaxation at high temperature reasonable values for the electronic exchange coupling parameter are obtained. Abstractde Messungen der Gitterparameter, der magnetischen Suszeptibilität und der 9Be-Kernresonanz und -Relaxation wurden an einer Reihe von intermetallischen Seltenen Erden–Beryllium-Verbindungen SEBe13 (SE = La, Ce, Nd, Gd) durchgeführt. Die anomalen Ergebnisse in CeBe13 lassen sich mit der Anwesenheit von verschiedenen Konzentrationen von Ce3+- und Ce4+-Ionen in der Probe mit einer Lebensdauer der Größenordnung 10−13 s erklären. Es wird gefunden, daß in NdBe13 Kristallfeldeffekte im untersuchten Temperaturbereich wesentlich sind, die bis herab zu 1,5°K magnetische Ordnung verhindern. GdBe13 wird bei ungefähr 22°K ferromagnetisch, jedoch ist die magnetische Suszeptibilität anomal unterhalb ungefähr 100°K. Sowohl in NdBe13 als auch in GdBe13 kann das asymmetrische 9Be-NMR-Spektrum bei hohen Temperaturen allein durch magnetische Dipolwechselwirkung der Kerne mit den paramagnetischen Momenten erklärt werden, während der isotrope Anteil der Verschiebung klein und negativ ist. Aus der 9Be-Spin–Gitter-Relaxation bei hohen Temperaturen werden vernünftige Werte für die elektronischen Austauschkopplungsparameter erhalten. Citing Literature Volume17, Issue216 June 1973Pages 631-642 RelatedInformation