NO for the two opposite orientations can be estimated. This anisotropy is consistent with what is found to explain the NO anisotropy in the desorption rate from Pt(lll). In addition, the anisotropy scales appropriately with the anisotropy of NO on Ag(lll), a considerably weaker molecule-surface interaction. The degree of anisotropy in this case is obtained from fitting scattered rotational quantum state distributions.28,29 The quality of the experiments allow an accurate modeling of the anisotropy and consequent dynamics. The falloff in sticking probability with J state, and by detailed balancing the high c/-state deficiencies in thermal desorption, is shown to be a general result of orientational anisotropy.25Molecular anisotropy is thus seen to play an important role in adsorption, via the rotational state dependence of (28) Muhlhausen, C. W.; Tully, J. C., private communicationunpublished results.(29) Kleyn, A.