Energy disposal in CN(A 2Π) produced in the 157 nm photodissociation of C2N2

Population distributions have been determined for the CN(A 2Π) product of the photodissociation of C2N2 at 157 nm. These were obtained through the use of a powerful method we have developed for the estimation of rotational state populations from complex overlapped laser-induced fluoresence spectra. The CN(A 2Π) vibrational populations decrease monotonically from v = 0 to 3 and are in qualitative agreement with the prior distribution. For each of v = 0–2, the rotational state populations are well described by phase space theory with an available energy 103 cm−1 less than the thermochemical value.