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Central problem=A08-m2b

In order to test the semiclassical calculation method [That method is given in the Theoretical methods (link type: 'is detailed in/focused in'; target: A08-m3cii)] and to test the suitability of the Landau-Zener theory for chemi-ionization in collision processes [That theory is given in the Theoretical methods (link type: 'focused in'; target: A08-m3ci)], the $\Na+\I\to\Na^++\I^-$ collision process is studied [More on the context of this research in the Situation module (link type: 'context in/essay-back/sq-back'); target: A08-m2a)] [More on the goal of the research in the mesoscopic Central problem module (link type: 'elaborated in/project/wider range); target: MESO-m2b)] [An answer to this central question in the Findings module  (link type: 'used in'; target: A08-m6a)].

For that purpose, relative differential cross sections are measured for the atom-atom collision process $\Na+\I\to\Na^++\I^-$ at kinetic energies from 13 to 85 eV, using atomic beam techniques [Particulars on those techniques in the Experimental methods (link type: 'is detailed in/focused in/essay-next'; target: A08-m3a)] allowing for the experimental resolution of interferences of two types, viz. the rainbow structure and the Stueckelberg oscillations More on the rainbow and Stueckelberg oscillations in Bernstein (link type: 'external/elaborated in/wider range'; target: MACRO-m3c-Bern)].

The measurements are then compared with semiclassical differential cross sections for the chemi-ionization calculated via the deflection curves, the Landau-Zener transition probability, the stationary-phase approximation and JWKB phase shifts, using estimations of the covalent potential parameters and the pseudocrossing parameter H12 based on the measurements. Calculations are performed both with and without taking into account the phenomenon of rotational coupling.