ALKALI METAL (LI, K) INDUCED RECONSTRUCTIONS OF THE W(001) SURFACE

The adsorption of Li and K atoms on the (001) surface of tungsten is found to exhibit remarkable differences in the surface core-level shifts (SCLS) of the W 4f level and in adsorbate-induced changes of the transition temperature of the substrate surface reconstruction. Density-functional theory calculations suggest that these results reflect mainly the different bonding geometry of the adatoms, and, for example, the adsorption of potassium is largely affected by an adsorbate-induced reconstruction of the substrate (dimerization of W atoms). (C) 1999 Elsevier Science B.V. All rights reserved.X111sciescopu