Dynamics of harpooning studied by transition state spectroscopy. Part III. Li···FCH3

Abstract

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Transition State Spectroscopy of the Photoinduced Ca + CH3F Reaction. 2. Experimental and Ab Initio Studies of the Free Ca···FCH3 Complex

“…As already noticed in the result section, these two potential branches show an analogy with those responsible for the LiF action spectrum in the Li · · · CH 3 F work of Polanyi and coworkers (compare Figure 7 of Ref. [5] to the present Figure 9). However, the detailed comparison between the two action spectra and more specifically the relative location of their most intense features with respect to the relevant potential branches suggests very substantial differences in the dynamics of the two reactions.…”

“…[5], including the anti-crossing that the upper curve undergoes with a higher Σ-like curve. In the present case, the 4s4p 1 P "Π" curve is stabilized by 2000 cm −1 with respect to the 4s4p 1 P asymptote.…”

“…The Na/HF [9], Li, Na/HF, CH 3 F [10,11,5], Na 2 /CH 3 Cl [12], Ca/HX [13,14,15,16] and Ba/CH 3 F [17,18,19,20,21,22] systems were explored using the latter technique. Realtime studies have also been performed on the Ba/CH 3 F system [23,24,25,26,27].…”

Transition State Spectroscopy of the Photoinduced Ca + CH3F Reaction. 1. A Cluster Isolated Chemical Reaction Study

“…Something new happens in the latter system that does not seem relevant of the local excitation that prevails in the Ca · · · HBr experiment. This is very unexpected not only because of the present comparison with the Ca · · · HBr system but also because local excitation of the metal moiety prevails in all the apparently similar complexes that were investigated so far: complexes between an alkali atom and halogen containing molecules [12,[42][43][44][45][46][47][48][49] or a complex between barium and CH 3 F [15,19,23,25]. Local excitation has also been found in many excited metal ion complexes such as Mg + CH 3 I described in Ref.…”

“…in the latter case, to the red of the resonance transition of Ca. In that case, the picture of the electronic excitation would be that of a fairly local electronic excitation of the metal atom in resemblance with the situation encountered with Li − CH 3 F [12] and Ba − CH 3 F [23] systems. Nevertheless, the present situation is still very different since, in contrast with the Li − CH 3 F and Ba − CH 3 F systems, a substantial kick has to be given to the C-F stretch of CH 3 F to turn on the Ca + CH 3 F reaction.…”