The diffusion of K on the polycrystalline Fe surface, modified by adsorbed O and N was studied by means of Auger emission spectroscopy. The migration of K atoms was observed independently on the Fe surface between 300 and 450C. The final concentration of K on the Fe surface increased from 300 to 400C, irrespective of what atoms accompanied K on the surface. At 450C, the final level of K concentration decreased. The profiles of the concentration on the surface, along a line crossing the source of K, were also determined. By applying the diffusion model for a finite source, the diffusion coefficient of K for O-covered and N-covered surfaces was evaluated.

Thermal Diffusion of Potassium on the Modified Iron Surface. U.Narkiewicz, D.Moszyński, M.Brosławski: Applied Surface Science, 2005, 252[3], 833-8