ADSORPTION OF NITROBENZENE AND SOME SIMPLE DERIVATIVES ON THE CU(110)SURFACE

Citation
Q. Chen et al., ADSORPTION OF NITROBENZENE AND SOME SIMPLE DERIVATIVES ON THE CU(110)SURFACE, Surface science, 368, 1996, pp. 310-317
Citations number
38
Categorie Soggetti
Chemistry Physical
Journal title
ISSN journal
00396028
Volume
368
Year of publication
1996
Pages
310 - 317
Database
ISI
SICI code
0039-6028(1996)368:<310:AONASS>2.0.ZU;2-O
Abstract
The chemistry of nitro- and amine-substituted aromatic molecules on a Cu(110) surface has been studied using Fourier transform infrared spec troscopy, by comparison of the adsorption of nitrobenzene (NB), p-dini trobenzene (pDNB) and p-nitroaniline (pNA). When nitrobenzene was adso rbed on a clean Cu(110) surface at room temperature, it decomposed to form a phenyl species with the C-2 axis nearer the surface normal than parallel. At 83 K, multilayer nitrobenzene formed with a vibrational spectrum, in good agreement with gas-phase data; upon warming, a pheny l species remained, which was stable to about 350 K. AES of the specie s present following dosing at 300 K showed carbon and oxygen but no ni trogen. When p-dinitrobenzene was adsorbed it decomposed, losing one N O2, to form a stable nitrophenyl species on Cu(110) orientated with th e C, axis closer to the surface normal than the phenyl species derived from nitrobenzene. In contrast, p-nitroaniline does not decompose on the Cu(110) surface at room temperature. Multilayer and monolayer p-ni troaniline are distinguished by frequency shifts of NO2 and NH2 modes, attributed to intermolecular hydrogen bonding. In the monolayer, the amine group appears to stabilise the ring-nitro group bond, allowing b onding to the surface via the NO2 group in an orientation perpendicula r to the surface.