Differential cross sections for state specific reactive scattering of Na–SF6→NaF–SF5

• Published in: The Journal of chemical physics 1996-03, Vol.104 (10), p.3620-3628
• Main Authors: Düren, R., Färber, M., Heumann, B., Knepper, M., Mohr, S., Weiss, C., Te Lintel Hekkert, S., Linskens, A. F., Reuss, J.
• Format: Article
• Language: English
• ISSN: 0021-9606; 1089-7690
• DOI: 10.1063/1.471064

Double-differential cross sections for the interaction of Na(3 2S) and Na(3 2P) with SF6 have been measured in crossed beam experiments for center of mass collision energies between 0.25 and 1.75 eV. In comparison with recently reported experiments the reaction with vibrationally excited SF6 is found to be more effective than the one with electronically excited Na. Results from an ab initio CASSCF calculation with Na in the ground state and the 3P state are presented. The experimental findings and the results from the calculation lead us to two different models for the reaction in the ground state and the excited state: While the well known harpooning model is verified for the ground state the reactive collisions with excited Na are mediated by nonadiabatic (nonreactive) transitions to the ground state surface. For these transitions the vibrational motion of SF6 is much more efficient than the relative motion in the collision.