Adsorption of phenyl isothiocyanate on Si(001): A 1,2-dipolar surface addition reaction

Citation
Md. Ellison et Rj. Hamers, Adsorption of phenyl isothiocyanate on Si(001): A 1,2-dipolar surface addition reaction, J PHYS CH B, 103(30), 1999, pp. 6243-6251
Citations number
56
Categorie Soggetti
Physical Chemistry/Chemical Physics
Journal title
JOURNAL OF PHYSICAL CHEMISTRY B
ISSN journal
15206106 → ACNP
Volume
103
Issue
30
Year of publication
1999
Pages
6243 - 6251
Database
ISI
SICI code
1520-6106(19990729)103:30<6243:AOPIOS>2.0.ZU;2-7
Abstract
The adsorption of phenyl isothiocyanate (PITC) on silicon (001) surfaces ha s been investigated using X-ray photoelectron spectroscopy (XPS), Fourier t ransform infrared (FTIR) spectroscopy, scanning tunneling microscopy (STM), and ab initio calculations. The experimental evidence shows that adsorptio n onto the Si surface occurs in a highly selective manner, through the N=C= S group and not through the benzene ring. Both experimental and theoretical evidence suggests that the adsorption involves the interaction of the N an d C atoms of the N=C=S group with the Si=Si dimer, forming a four-member Si 2NC ring at the interface. This process leaves the aromatic ring nearly unp erturbed and is analogous to a 1,2-dipolar addition reaction. Theoretical c alculations confirm that this is the most stable product.