On the stay time of Rb + ions in the outermost layer of the (100) surface of NaCl

Abstract

Desorption transients of RbCl from (100) surfaces of NaCl are studied for a crystal temperature T = 603 K and for impinging RbCl fluxes j on Rb = 2.3 × 10 10-2.0 × 10 12 cm −2 s −1 without and with additional NaCl fluxes j on Na = 2.5 The time constants τ of the transients show a dependence on j on Rb and j on Na . As was shown earlier [Surf. Sci. 218 (1989) 519] dependence of τ on j on Rb is given by τ=( 1 τ 0 + j on Rb n max ) −1 , where n max = 2.3 × outermost layer of the NaCl crystal for Rb +. The time constant τ 0 proves to be inversely proportional to the mean admolecule concentration of NaCl on the surface. Deviations from this proportionality are found in the region of two-dimensional nucleation.