Surface cars spectroscopy of pyridine and phenol on ZnO optical waveguides

✍ Scribed by William M. Hetherington III; Zonh-Zen Ho; Edward W. Koenig; George I. Stegeman; Rance M. Fortenberry

• Publisher: Elsevier Science
• Year: 1986
• Tongue: English
• Weight: 518 KB
• Volume: 128
• Category: Article
• ISSN: 0009-2614
• DOI: 10.1016/0009-2614(86)80315-3

✦ Synopsis

Using planar optical waveguide geometry, surface CARS spectra of phenol and pyridine adsorbed on ZnO surfaces have been observed under high-vacuum conditions. When most of the CARS contribution from the ZnO film was eliminated by an interference condition, submonolayer quantities were detectable. The Y,* mode of phenol is insensitive to the nature of the surface bond and leads to a single line at 1002 cm -'. The Y, mode of pyridine gtves rise to three lines at 993, 1000 and 1008 cm-' corresponding to sites for physrsorption, hydrogen-bonding and protonation. At high surface power densities, photoinduced desorption of pyridine was observed. Two-photon absorption m the ZnO leads to a power-dependent index of refraction.