EJECTION OF CN(A) FROM CN(B)-AR-N CLUSTERS AND THE RADIATIVE LIFETIMEOF 7-LESS-THAN-OR-EQUAL-TO-V-LESS-THAN-OR-EQUAL-TO-9)

Electronic predissociation of CN(B)-Ar-n, (n approximate to 100) clust ers has been examined using optical-optical double resonance technique s. Rotationally cold (T-rot approximate to 130 K) CN(A, upsilon=9) fra gments were detected following excitation of CN(B,upsilon=0)-Ar-n. An upper bound for the predissociation rate of Gamma(p)<2 x 10(6) s(-1) w as determined. These results are consistent with a surface-bound struc ture for the CN-Ar-n clusters, or a sequential dissociation process th at involves a surface-bound intermediate. Demonstration that free CN(A ) is produced by predissociation of CN(B)-Ar-n, validates a previous d etermination of the radiative lifetime for CN(A)7 less than or equal t o upsilon less than or equal to 9 levels. (C) 1998 American Institute of Physics.