Local electronic structure of intrinsic defects and impurities at the Fe(001) surface

Abstract

Local electronic structure of intrinsic defects and impurities at the Fe (001) Take-down policy If you believe that this document breaches copyright please contact us providing details, and we will remove access to the work immediately and investigate your claim.Downloaded from the University of Groningen/UMCG research database (Pure): http://www.rug.nl/research/portal. For technical reasons the number of authors shown on this cover page is limited to 10 maximum. AbstractAb-initio calculations for the electronic structure and magnetic properties of intrinsic defects and foreign impurities (oxygen and gold) on the Fe(001) surface using the LSW method and the super-cell approach are presented. The calculations show that the Fe intrinsic defects have different local density of states. The magnetic moment of the Fe substrate layer under the defects increases with decreasing number of nearest neighbors of the surface, while the magnetic moment of the Fe defects decreases with decreasing number of nearest neighbors on the surface. The oxygen impurities have rather narrow (2p) bands at about 6.0 eV below the Fermi energy. The influence of oxygen impurities on the Fe(001) surface states near the Fermi energy is remarkably insignificant. Both gold and oxygen impurities have small magnetic moments parallel to the surface iron.

Stability, structure and electronic properties of γ-Fe23C6 from first-principles theory

“…As shown in Table 3, Fe2 atoms have only four nearest-neighboring Fe3 atoms. This agrees with the fact that reduction of the number of nearest-neighboring and/or next nearest-neighboring atoms increases local magnetic moments, as shown for the surface Fe atoms in the literature [44]. The Fe3 atoms are neighboring to 10 Fe and 3 C atoms, which is similar to the Fe atoms in hFe 3 C. The magnetic moment of Fe3 atoms is 1.78 l B , a value which is the smallest in the compound and is close to that in h-Fe 3 C. Fe4 atoms also have 10 Fe neighbors ranging from 2.38 to 2.61 Å , and two C neighbors (Fe-C bond of 2.10 Å ).…”

“…For all iron atoms, the Fermi level is at the top of the Fe 3d states for the spin-up electrons. Therefore, the Fe atoms are almost fully spin-polarized, in line with electronic structure of a-Fe [44,45].…”

“…Such a high value occurs for Fe atoms at surfaces, e.g. the (0 0 1) surface of a-Fe [44], but rarely in bulk metals. As shown in Table 3, Fe2 atoms have only four nearest-neighboring Fe3 atoms.…”

Spin-polarized scanning tunneling microscopy and spectroscopy study of c(2×2) reconstructed Cr(001) thin film surfaces

“…7 Another possibility is that it originates from different chemical species, carbon or oxygen atoms. 15 However, the latter one is excluded since the difference of the chemical species must lead to that of the surface state energy as well as the peak intensity.…”

“…Impurity atoms, e.g., carbon and oxygen, included in bcc-͑001͒ surfaces shift the surface state energy. 14,15 Other origin is that confinement effect induced by surface atomic arrangements gives rise to the surface state shift. Biedermann et al showed that one-dimensional localization of Fe atoms, which was surrounded by Si atoms on FeSi͑001͒ surfaces, induced surface state shift from 0.3 to 0.6 eV above the Fermi level.…”