An Investigation of Ethylene Attachment to Si(111)-7 x 7 in the Restatom-Adatom Bridging Geometry: Electronic and Vibrational Properties

作者：Majzik Z^*; Kaminski W; Weymouth A J; Vondracek M; Zobac V; Svec M; Berko A; McLean A B; Prince K C; Jelinek P; Chab V

来源：Journal of Physical Chemistry C, 2011, 115(44): 21791-21799.

DOI：10.1021/jp206337w

The adsorption of ethylene on the bridge adatom-restatom position of the Si(111)-7 x 7 surface was studied with scanning tunneling microscopy, photoelectron spectroscopy, and theoretical calculations. The electronic structure and the corresponding vibrational states were calculated for a single molecule adsorbed in different binding sites located within the 7 x 7 unit cell. We found that there is no significant difference in the electronic structure between the absorption sites that were considered: center and corner adatom-restatom. Moreover, the different electron occupation of the restatoms and adatoms has a strong effect on the electronic structure of the adsorbed molecule near the Fermi level, and this leads to the reduction of the molecular symmetry to C-s or even to C-1. In the case of the Si 2p core level, beside the previously reported continuous quenching of the restatom state, we found clear evidence of existence of a peak corresponding to the Si-C bond separated by 044 eV from the bulk component Furthermore, for the vibrational analysis, isotopic substitution of C2H4 with C2D4, gave Us More insight into the correct assignment of the modes in the experiment. Specifically; exceptional care Must be taken with the allocation of the C-H wagging, twisting, and C-C stretching modes.

• 出版日期2011-11-10