Photodissociation fragment angular distribution

Another possibility for distinguishing between direct and indirect channels arises from an analysis of the angular dependence of the fragments. If the photodissociation is direct, there will be a correlation between the angular distribution and and direction of the radiation. For indirect photodissociation the correlation vanishes, because the appearance of the photofragments is a result of the radiationless transition. 

Several papers have been written on the subject of analyzing the anisotropic distribution of v and j vectors of molecules produced by a photodissociation reaction [17,36-42]. The most satisfying scheme is the renormalized bipolar moment analysis proposed by Dixon [18]. The basic premise is to use bipolar harmonics as the basis set to describe the angular distribution of a single recoil velocity v and fragment angular momentum j ... 

Photofragment spectroscopy.—The analysis of the angular distribution and energies of fragments arising from photodissociation, using polarized light, permits evaluation of the states involved in the dissociation process and an approach towards the ideal experiment in which microscopic reaction rates can be measured, and there has been much increased interest in this phenomenon in the past year, both from an experimental and theoretical standpoint. Papers... 

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