title: Two- and three-body photodissociation dynamics of diiodobromide (I2Br-) anion.
abstract: The photodissociation of gas-phase I(2)Br(-) was investigated using fast beam photofragment translational spectroscopy. Anions were photodissociated from 300 to 270 nm (4.13-4.59 eV) and the recoiling photofragments were detected in coincidence by a time- and position-sensitive detector. Both two- and three-body channels were observed throughout the energy range probed. Analysis of the two-body dissociation showed evidence for four distinct channels: Br(-) + I(2), I(-) + IBr, Br+I(2) (-), and I + IBr(-). In three-body dissociation, Br((2)P(3∕2)) + I((2)P(3∕2)) + I(-) and Br(-) + I((2)P(3∕2)) + I((2)P(3∕2)) were produced primarily from a concerted decay mechanism. A sequential decay mechanism was also observed and attributed to Br(-)((1)S)+I(2)(B(3)Π(0u) (+)) followed by predissociation of I(2)(B).
authors.affiliation: Department of Chemistry, University of California, Berkeley, California 94720, USA.
authors.forename: Paul E
authors.initials: PE
authors.lastname: Crider
authors.forename: Aaron W
authors.initials: AW
authors.lastname: Harrison
authors.forename: Daniel M
authors.initials: DM
authors.lastname: Neumark