Field emission fluctuations of the adsorption system, K/(112)W, were investigated by using the cross-correlation technique and a field emission tube with a variable distance between the probed regions. At high temperatures, the adsorbate behavior could be described by a standard diffusion model. The results were used to determine approximate diffusion parameters. It was deduced that K surface diffusion along a [111]-type crystallographic direction on the (112) plane could be described by:

D (cm2/s) = 4.0 x 10-2 exp[-0.70(eV)/kT]

J.Beben, C.Kleint, R.Meclewski: Surface Science, 1989. 213[2-3], 438-50