Incorporation of sulphur into the (111) surface of nickel?
Abstract
With the aim of monitoring coverage-dependent adsorbate coordination, we have studied the polarisation-dependent S K-edge SEXAFS of p(2 × 2)S and ( 5 3 × 2) S overlayers on Ni(111). The data indicate S bonding to the three-fold hollow sites in the p(2 × 2)S phase, with a SiNi bond distance of 2.23 ± 0.02 Å. In the higher coverage, ( 5 3 × 2) S phase the S-Ni distance is 2.27 ± 0.02 Å. The Ni(111)(5 3 × 2) S results are compared with those expected on the basis of the three proposed structural models of this surface. The data are consistent with only one of these models, in which S occupies rectangular hollow sites in a pseudo-Ni(100)c(2 × 2)S overlayer.
- Publication:
-
Surface Science
- Pub Date:
- April 1989
- DOI:
- 10.1016/0039-6028(89)90755-3
- Bibcode:
- 1989SurSc.211...71W