NUCLEAR-SPIN RELAXATION OF LI-8 ADSORBED ON SURFACES

Nuclear spin relaxation experiments with Li-8 adsorbed on various surf aces provide new information in surface science which is not obtainabl e othervise. Both dipolar (Korringa) and quadrupolar relaxation due to diffusion are observed. However, in addition, a fast and presently no t understood spin relaxation mechanism is present while dosing during the first 0.5 s the surface with polarized Li-8. Most strange in this respect is the fact that those Li-8 atoms which survive depolarization through this mechanism depolarize afterwards with modest spin lattice relaxation rates. The origin of the fast spin lattice relaxation mech anism is presently unknown.