Velocity selected laser polarization spectroscopy: a powerful and versatile method of obtaining the state-to-state differential cross section

Two-colour, velocity selected laser polarization spectroscopy is shown to be a powerful new technique for obtaining state-to-state differential cross sections (dcs) for inelastic collisions of molecules in their ground states. Preliminary results are presented for X1Σg+Li2-Xe, Ar and X1Σg+Na2-Xe, Ar and show the dynamics of the two alkali dimers to be strikingly different from one another. The quality of the X1Σg+Na2-Xe data permits extraction of the most porbable scatterin angles. These are compared to published rotationally inelastic state-to-state dcs for X1Σg+Na2-Ne and encouraging agreement is found.