Chemisorption structure of c(2×2)S/Fe(001) determined by angle-resolved photoemission extended fine structure.

Autor: Zhang, X. S., Terminello, L. J., Kim, S., Huang, Z. Q., Schach von Wittenau, A. E., Shirley, D. A.
Předmět:
Zdroj: Journal of Chemical Physics; 11/15/1988, Vol. 89 Issue 10, p6538, 9p
Abstrakt: An accurate chemisorption geometry was determined for the c(2x2)S/Fe(001) system using the angle-resolved photoemission extended fine structure (ARPEFS) method, with S(1s) photoelectron peak intensities observed along [001] and [011]. Multiple-scattering spherical-wave analysis confirmed the LEED-derived fourfold hollow site geometry, and yielded perpendicular distances for S of 1.09(2) Å above the first layer and 2.50(2) Å above the second layer atom directly below S. The S–Fe nearest-neighbor bond length is 2.30(1) Å and the M–S–M bond angle is 123(1)°. The Fe1 –Fe2 interlayer distance is contracted to 1.40(2) Å and the Fe2 –Fe3 distance expanded to 1.46(3) Å, relative to the bulk value of 1.43 Å. The results are compared with similar systems and partially explained on chemical grounds. The derived structure agrees with the results of a self-consistent field (SCF) Xα spherical wave (SW) calculation. [ABSTRACT FROM AUTHOR]
Databáze: Complementary Index