Temperature-dependent photodissociation dynamics of ICN at 262 nm

Transient frequency-modulation (FM) Doppler spectroscopy has been used to m easure scalar and vector correlations in state-selected CN fragments arisin g from the photodissociation of ICN at 262 nm at both 296 and 550 K. We fin d that the state-selected I*/I branching ratio changes significantly with i ncreased temperature, consistent with the increased width of the state-depe ndent CN rotational distribution. However, we find little change in the sta te-selected vector properties suggesting that thermal modification of the i nitial parent vibrational distribution is not a sensitive means to probe th e nonadiabatic dynamics. (C) 2001 Elsevier Science B.V. All rights reserved .