Affordable Access

The first layer of water on Rh(111): microscopic structure and desorption kinetics.

Authors
  • Beniya, Atsushi
  • Yamamoto, Susumu
  • Mukai, Kozo
  • Yamashita, Yoshiyuki
  • Yoshinobu, Jun
Type
Published Article
Journal
The Journal of chemical physics
Publication Date
Aug 07, 2006
Volume
125
Issue
5
Pages
54717–54717
Identifiers
PMID: 16942251
Source
Medline
License
Unknown

Abstract

The adsorption states and growth process of the first water (D2O) layer on Rh(111) were investigated using infrared reflection absorption spectroscopy, temperature programed desorption, and spot-profile-analysis low energy electron diffraction. Water molecules wet the Rh(111) surface intact. At the early stage of first layer growth, a (square root 3 x square root 3)R30 degrees commensurate water layer grows where "up" and "down" species coexist; the up and down species represent water molecules which have free OD, pointing to a vacuum and the substrate, respectively. The up domain was a flatter structure than an icelike bilayer. Water desorption from Rh(111) was a half-order process. The activation energy and the preexponential factor of desorption are estimated to be 60 kJ/mol and 4.8 x 10(16) ML(1/2)/s at submonolayer coverage, respectively. With an increase in water coverage, the flat up domain becomes a zigzag layer, like an ice bilayer. At the saturation coverage, the amount of down species is 1.3 times larger than that of the up species. In addition, the activation energy and the preexponential factor of desorption decrease to 51 kJ/mol and 1.3 x 10(14) ML(1/2)/s, respectively.

Report this publication

Statistics

Seen <100 times