title: Slice imaging of the photodissociation of acetaldehyde at 248 nm. Evidence of a roaming mechanism.
abstract: The photodissociation of acetaldehyde in the molecular channel yielding CO and CH(4) at 248 nm has been studied, probing different rotational states of the CO(nu = 0) fragment by slice ion imaging using a 2+1 REMPI scheme at around 230 nm. From the slice images, clear evidence of the co-existence of two different mechanisms has been obtained. One of the mechanisms is consistent with the well-studied conventional transition state in which CO products appear rotationally excited, and the second is consistent with a roaming mechanism. This roaming mechanism is characterized by a low rotational energy disposal into the CO fragment as well as by a very low kinetic energy release, corresponding to a high internal energy in the CH(4) counter-fragment.
authors.affiliation: Institute of Electronic Structure and Laser, Foundation for Research and Technology--Hellas, P.O. Box 1527, 711 10, Heraklion-Crete, Greece.
authors.forename: L
authors.initials: L
authors.lastname: Rubio-Lago
authors.forename: G A
authors.initials: GA
authors.lastname: Amaral
authors.forename: A
authors.initials: A
authors.lastname: Arregui
authors.forename: J G
authors.initials: JG
authors.lastname: Izquierdo
authors.forename: F
authors.initials: F
authors.lastname: Wang
authors.forename: D
authors.initials: D
authors.lastname: Zaouris
authors.forename: T N
authors.initials: TN
authors.lastname: Kitsopoulos
authors.forename: L
authors.initials: L
authors.lastname: Bañares