Spin–orbit effects in the luminescent charge-transfer reaction F++CO

Abstract

In an ion beam study of the luminescent charge-transfer reaction F+(3P0,1,2)+CO(X 1Σ+)→F(2P1/2,3/2) +CO+(A 2Π1/2,3/2), the product CO+(A) emission spectra have been examined at a collision energy of 11.9 eVCM, using high (∼1 Å FWHM) optical resolution. For the near-resonant vibrational level v′=5, the 2Π3/2 S/O component of CO+(A) was found to be formed with an excess population of ∼40% relative to the 2Π1/2 component. Lower-resolution data show a similar enhancement of 2Π3/2 also for the v′=6 level, but not for v′=4 and 3. This can be rationalized in terms of recent ab initio calculations. Also in accordance with these calculations, the product rotational excitation was found to be very low in the v′=5 level. The best-fit rotational ‘‘temperature’’ is for this level actually less than the target gas temperature, a common artifact in collisional processes with small angular momentum transfer.