Rainbow scattering of CO and N2 from LiF(001)

• Published in: The Journal of chemical physics Vol. 122; no. 24; p. 244713
• Main Authors: Kondo, Takahiro, Kato, Hiroyuki S, Yamada, Taro, Yamamoto, Shigehiko, Kawai, Maki
• Format: Journal Article
• Language: English
• Published: United States 22.06.2005
• ISSN: 0021-9606
• DOI: 10.1063/1.1944729

The angular intensity distributions of CO and N(2) molecules scattered from a LiF(001) surface have been measured as functions of surface temperature, incident translational energy, and incident azimuthal direction affecting surface corrugation at a high resolution. Although both molecules have the same molecular mass and linear structure, only the CO molecule shows a rainbow feature in its scattering pattern, while the N(2) molecule shows a single peak distribution. From the comparisons of the obtained results with the calculated predictions based on the newly developed classical theory of the ellipsoid-washboard model, the differences in scattering distribution are attributed to the effects of molecular anisotropy and center-of-mass position. With an increase in the extent of the molecular anisotropy such as that of N(2) and CO as compared with rare-gas atoms, the summation of several scattering distributions depending on molecular orientation results in smearing the rainbow scattering on the corrugated surface. This smearing effect, however, attenuates when center-of-mass position deviates from the molecular center, as that for CO.