Adsorption of Se on Fe(110) and Fe(100). An Ab-Initio Study

CARDOSO SCHWINDT, VIRGINIA; BECHTHOLD, PABLO; GONZALEZ, ESTELA; JASEN, PAULA; JUAN, ALFREDO; BARBARA SETINA BATIC; MONIKA JENKO

Portoroz

Congreso; 22th Internacional Conference on Materials and technology; 2014

The adsorption of atomic Se on the Fe (100) surface is examined using density functional theory (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 (Figure 1) and the bridge site result to be instable. The Se adsorption not results in a surface reconstruction as we found in the (110) surface previously reported. 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 second Fe layer atoms. 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.