Alkali-metal atoms scattering experiments

Crossed molecular beams have been used to study nearly as wide a range of alkali metal atom reactions as has been examined by diffusion flames. An excellent review has been provided by Herschbach2. The multi-step mechanism displayed for chemiluminescence studies does not apply to the scattering experiments. Only the initial bimolecular reaction is important at the low pressures used. 

Ion-impact excitation has been widely studied in the rare gases260 270 and for alkali metal ion-atom collisions.271 280 In many cases excitation functions have been measured (i.e., total cross sections as a function of initial relative translational energy), and in some instances the angular dependencies of the differential cross sections for inelastic scattering have been determined. The most striking feature of the results from these experiments is the oscillatory structure that is evident in many of the... 

As indicated in Section III.B, the multiphonon scattering can also be investigated and interpreted in terms of the atom-surface potential. Most of this work has been carried out with alkali halides, but some experiments have also been done using metals. Figure 29 shows the typical behavior seen for... 

Since the first age of molecular beam scattering there has been a constant interest in the dynamics of metal atom-molecule reactive collisions. The effect of relative translational energy of reagents on reaction dynamics has been extensively studied. However a great majority of experiments has been devoted to alkali and alkali-earth reactions. The insight into the reactivity of other metal elements is comparatively less rich and this can be easily connected with the technical constraints associated with the generation of beams of these atoms. 

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