Magnetic Behavior of Intermetallic Compounds of Beryllium

Abstract

The corroboration by NMR of the ferromagnetism of CrBe12 has prompted an NMR investigation of the magnetic properties of other beryllium intermetallic compounds. Magnetic-moment measurements of these materials show complex magnetic behavior at 4.2°K. All samples show strong paramagnetic moments and many exhibit remanence. To provide more information on this magnetic behavior, the 9Be resonance was observed in the following samples, listed in approximate order of their magnetic strength at 4.2°K: CrBe12, ZrBe2, MnBe8, FeBe11, MnBe12, NbBe3, ZrBe13, TaBe3, CrBe2, Nb2Be17, TiBe12, NbBe12, VBe12, MoBe12, TaBe12, WBe2, Ta2Be17, WBe12. Magnetization measurements are also reported for AgBe12, FeBe12, CoBe12, PtBe12, PdBe12, and AuBe12. Both the Knight shifts and the linewidths show correlation with the moment measurements. Most of the samples show small magnetic moments, positive Knight shifts, and small linewidths, ΔH, less than (800 A/m=10 Oe). ZrBe2 and MnBe8 have larger moments, negative values of K (∼−0.03% at 300°K) and larger ΔH [∼(1.2 kA/m=15 Oe) at 300°K]. CrBe12, clearly ferromagnetic, with the largest moment (of the compounds studied) has the most negative value of K (−0.19% at 300°K) and the largest ΔH [(1.83 kA/m=23 Oe) at 300°K]. From the temperature dependence of the linewidths, it appears that NbBe3 and CrBe2 may be magnetic, although much weaker than CrBe12. Anisotropic Knight shifts and first-order quadrupole effects are noted.