Adsorption of Se on Fe(100). An ab-initio study

CARDOSO SCHWINDT, VIRGINIA; BECHTHOLD, PABLO; ARDENGHI, SEBASTIAN; GONZALEZ, ESTELA; JASEN, PAULA; A. JUAN; BARBARA SETINA BATIC; JENKO MONIKA

Viena

Congreso; 15th Joint Vacuum Conference; 2014

The adsorption of atomic Se on a Fe(110) surface is examined using the density functional theory (DFT). Selenium is adsorbed in high-symmetry adsorption sites: the -short and long-bridge, and atop sites at 1/2, 1/4, and 1 monolayer (ML) coverages.The adsorption of atomic Se on the Fe (100) surface is also examined by DFT. Selenium is adsorbed in the high-symmetry adsorption sites: bridge, 4-fold hollow and atop sites in coverage of 1/2, 1/4 and 1 monolayer (ML). The 4-fold hollow site is found to be the most stable and the bridge site result to be unstable. The Se adsorption do not result in a surface reconstruction as we previously found for the (110) surface [1]. Comparisons between Se-adsorbed and pure Fe surfaces revealed reductions in the magnetic moments of surface-layer Fe atoms in the vicinity of the Se as in the previous surface analysed. The density of states present a contribution of Se states at -5.0 eV and -13.2 eV stabilized after adsorption. Se atom extends its interaction up to the second Fe layer. In this study, the Se almost no presents magnetization. The Fe-Fe overlap population decrease and a Fe-Se bond are formed at expenses of the metallic bond