CHARACTERIZATION OF CN IN THE PHOTODISSOCIATION OF CYANOGEN AZIDE AT 193-NM

The photodissociation dynamics of NCN3 has been investigated by observ ation of the CN(X2SIGMA) product molecule. The CN fragment is formed i n vibrational states upsilon = 0,1,2 with a population ratio of P(upsi lon = 0):P(upsilon = 1):P(upsilon = 2) = 0.42:0.33:0.25. The rotationa l state distribution is broad, a Boltzmann plot shows a nonlinear beha vior. The rotational excitation carries 9% of the available energy. Th e CN recoil velocity distribution is also broad and indicates a signif icant internal excitation of the N3 product molecule. The spin is dist ributed statistically. The fragmentation does not proceed in the Franc k-Condon limit but strong forces act on the upper potential energy sur face.