Cesium and rubidium vapors adsorption by metallic surfaces in vacuum

Quantities of cesium and rubidium which are absorbed by nickel, aluminium and tantalum foils at 160-220 deg C and a vapour pressure of 2x10-4-5x10-7 atm have been determined. Thermodynamic data have been used to explain the results obtained. Chemical surface reactions have been shown to play the principal role in absorption processes. These reactions result in formation of alkali metal oxides on the surface. The limiting values of cesium and rubidium adsorption on tantalum correspond to absorption of practically the same quantities of atoms of the alkali element: (3.16+-0.15)x10-2 g.-at.Cs/cm"2 and (3.05+-0.12)x10-2 g.-atm.Rb/cm"2