A new perspective on isomerization dynamics illustrated by HCN->HNC

We discuss the role of delocalized states in isomerization dynamics and illustrate the ideas by considering isomerization in HCN. We analyze results from an earlier study, when HCN was treated as a semirigid bender, and isomerization was induced by collision with an Ar atom. That analysis is applied here to three-dimensional HCN, using exact three-dimensional wave functions, obtained using a slight modification of a previous global potential based on high-quality ab initio calculations.