Relaxation of vibrationally excited cs produced in the reaction: O(3P)+ CS2→ SO + CS
Abstract
Vibrationally excited CS, in its electronic ground state, has been formed in the flash-initiated reaction, O(3P)+ CS2→ SO + CS, and its relaxation observed by kinetic absorption spectroscopy. The average number Z1,0 of collisions required to de-excite CS(v= 1) has been calculated for a number of collisional partners, and the following values obtained: NO2, 8 × 102; CS2, 1.8 × 104; Ar, > 106; He, 2.0 × 105; H2, 8.3 × 103; D2, 5.5 × 104; N2O, 2.9 × 102; CO2, 5.0 × 103; but-1-ene, 80. The efficiencies of the triatomic species are best explained in terms of vibrational exchange to the fundamental mode most closely in resonance with the CS vibration. The relative values of Z1,0 for He, H2 and D2 indicate that vibrational-rotational energy transfer may be important with H2 and D2.