Short-wavelength photlysis of jet-cooled OClO(~2A_2v_1 20) - ClO(X~2II_#OMGEA#, v, J) + O (~3P_J)

摘要

Highly inverted vibrational .levelpopulatiohs are found for ClO fragments resulting from the UV photodissociation of OClO(2A2 vI >20) into ClO(X2nn,v,J) and 0(3pJ) fragments. These distributions depend significantly on the spin-orbit J state of the oxygen 0(3p J) partner atom. In contrast, the ClO rotational excitation is modest. Distinct rotational structure is visible in the 0 (3 p ? photofragment yield spectrum ~ecorded from the highly excited OClO (2 A2 VI = 21) vibronic band, which is indicative for hitherto unforeseen long dissociation lifetimes of very highly excited OClO. The data point towards an unexpected nearly-linear and highly asymmetric dissociation geometry. Carrying out near-threshold fragmentation experiments of OClO (2A20,0,0) ~CIO (X 2n3/2 v = 0, J)+ 0(3 P2,I,O) the dissociation energy Do of OClO has been accurately, determined to 247.3:t 0.5 kJ/mol.