Ti and Be NMR Studies of a Nearly Ferromagnet TiBe₂

Abstract

The microscopic magnetic properties of an itinerant electron paramagnet TiBe₂ have been investigated by Ti and Be NMR at temperatures from 1.4 to 280 K. The Knight shift K of the Ti resonance was found to be linear in the susceptibility χ, while the temperature and the external field dependences of the Be resonance spectrum could be explained consistently from the combined effect of anisotropic hyperfine and electric quadrupole interactions. From the analysis of the Knight shift and the nuclear spin-lattice relaxation time T₁ of Be at low temperatures, it is shown that only the long-wave components of spin fluctuations are strongly exchange-enhanced and play a predominant role. It is also shown that although the spin contribution to 1⁄T₁ varies above about 40 K as χ_spinT in accord with a theoretical calculation for weakly or nearly ferromagnetic metals, deviation from the above relation is quite marked at lower temperatures.