Nuclear Magnetic Resonance ofPt195and Satellite Structure in Pt-Rich Pt-Mo Alloys

An NMR investigation of ${\mathrm{Pt}}^{195}$ in Pt-based alloys with Mo reveals the presence of satellites as well as large decreases in metallic shift versus Mo concentration. A "local" spin density with a relatively long range is thought to account for these phenomena. The results also suggest large reductions per Mo atom in the bulk susceptibility. One finds that the rigid-band model seems not to explain the data, and a "distorted" band or a weakening of the exchange enhancement must instead be considered. In the Appendix, previously reported NMR results on Pt in Pt-Ir alloys are discussed in the light of some newly discovered contaminants.