Structural study of metals in the vicinity of their surfaces

Foils of chemically pure Mo, Pt and He ranging in thickness from several to decades of microns were used to establish the variation of the temperature coefficient of electric resistance of a conductor with its rising temperature under normal external pressure. This variation depends on the specimen thickness and is non-existent under external pressure < or approximately 10-4 mm of mercury column. The observed effects indicate that under normal external pressure the structural state of metals in the surface-adjoining layer is different compared to their volume, and this layer increases in thickness with rising specimen temperature. In vacuum these phenomena disappear