15min:

N. BARTELS, T. SCHÄFER, J. HÜHNERT, A. M. WODTKE, Georg August Universität Göttingen, Institut für Physikalische Chemie, Tammanstrasse 6, 37075 Göttingen, Germany; AND R. W. FIELD, Massachusetts Institute of Technology, 77 Massachusetts Avenue, Cambridge, MA 02139, USA.

\beginwrapfigure[20]r8cm \vspace-.5cm \hspace*-0cm \epsfigfile=Bild4.eps \endwrapfigure

For many experimentalists (especially those, who are not spectroscopists), molecular pertubations are a curse, as they make assignments and analysis of spectral data more difficult. Nevertheless, they can also be a boon! \newline In this talk we will show how a molecular beam of CO in high vibrational states (v=17,18) can be prepared by an optical pumping scheme that we call PUMP-PUMP-PERTURB and DUMP (P³D). P³D exploits the loaning, via spin-orbit perturbations, of the large oscillator strength of the 4th positive system, A ¹ X ^{1 +}, to the triplet manifold. This allows some nominally spin-forbidden transitions to be exploited in multistep optical pumping schemes. \newline The ability to state-selectively prepare CO in high vibrational states opens up new opportunities for molecular beam scattering experiments.