15min:

YALING CHEN, WILLIAM G. LAWRENCE AND MICHAEL C. HEAVEN, Department of Chemistry, Emory University, Atlanta, GA 30322.

CN-Ar_n clusters with an average size of n=100, were prepared in a supersonic expansion. Electronic excitation of the clusters to CN(B²⁺)-Ar_n was followed by electronic predissociation. In a previous low-resolution study, it was proposed that predissociation involved the ejection of free CN(A²) from the surface of the cluster. In the present work, OODR techniques were used to demonstrate that free CN(A²) was produced. Interestingly, although a natural isotopic mixture of CN was used (1% ¹³CN), similar quantities of ¹²CN and ¹³CN fragments were detected. The product state distributions resulting from predissociation, and the isotopic selectivity of the dynamics will be discussed.