Molecular Beam Photoinduced Reactions

Even the homolytic dissociation of a very simple molecule reveals an unexpected wealth of information in time-of-flight translational spectroscopy. The molecule S02 undergoes dissociation when excited with far UV light (193 nm) 

The detailed mechanism of the dissociation of formaldehyde (H2CO) has been investigated in molecular beam experiments. The reaction itself may appear quite simple 

A third quite different reaction has also been observed in these molecular beam experiments the direct formation of H2 according to 

This must be a concerted process rather than a secondary dissociation of formaldehyde or hydroxymethylene from the previous reactions, because of the high energy barriers of these secondary dissociations. 

2 Spectral Resolution with Large Molecules. Although most molecular beam studies deal with small molecules, there are some observations of reactions of 

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