INVESTIGATION OF THE EFFECT OF OXYGEN IMPURITIES ON THE WETTING PROPERTIES OF ALKALI-METAL SURFACES BY LIQUID-HELIUM

The weak: binding properties of heavy alkali metal surfaces for helium have been related to their metallic nature and their particularly sma ll work function. A natural consequence would be that oxidized surface s should loose their non wetting properties for liquid helium. It is p ointed out that the special oxidization process of these metals could unexpectedly lead to an opposite result at some intermediate stage. Fi rst experimental results on rubidium shows evidences for such an effec t.