LASER PHOTODISSOCIATION OF KETENE AT 230 NM

Ketene in a molecular beam is excited at the onset of its (X) over til de(1)A(1) -->, (B) over tilde(1)B(1), absorption band by laser light a t 230 nm, The rovibrational population distribution in the CO photofra gment, formed in the dissociation, is probed by REMPI. The phase space theory (PST) is applied to the dissociation channels leading respecti vely to CO + CH2((a) over tilde(1)A(1)) and CO + CH2((b) over tilde(1) B(1)). For the latter, the PST calculations lead to an average rotatio nal energy in CO which is not compatible with the measured value, thus suggesting that this channel does not represent an important contribu tion to the dissociation process. (C) 1998 Elsevier Science B.V. All r ights reserved.