Nuclear Spin-Lattice Relaxation in Cadmium and Tin

Pulsed nuclear-magnetic-resonance measurements of the spin-lattice relaxation time T₁ in Cd¹¹³ and Sn¹¹⁹ from 77 to 820^∘{}K are reported. An enhancement of the Korringa product T₁TKᵢₛₒ^_² that is constant with temperature but different in the solid and liquid states is observed. For Cd¹¹³, the difference between the liquid and solid enhancement is significant and can be related to a core-polarization or orbital contribution to the isotropic Knight shift Kᵢₛₒ. In solid Cd¹¹³, the sum of these two contributions to Kᵢₛₒ is about -9% as large as the contribution from the contact hyperfine interaction and that fraction is independent of temperature. In liquid Cd¹¹³ and solid and liquid Sn¹¹⁹, the sum of these contributions is probably small.