title: Vibrational energy transfer in O2(X 3sigma(g)-, upsilon=2,3) + O2 collisions at 330 K.
abstract: Vibrational relaxation of O2(X 3sigma(g)-, upsilon=2,3) by O2 molecules is studied via a two-laser approach. Laser radiation at 266 nm photodissociates ozone in a mixture of molecular oxygen and ozone. The photolysis step produces vibrationally excited O2(a 1delta(g)) that is rapidly converted to O2(X 3sigma(g)-, upsilon=2,3) in a near-resonant adiabatic electronic energy-transfer process involving collisions with ground-state O2. The output of a tunable 193-nm ArF laser monitors the temporal evolution of the O2(X 3sigma(g)-, upsilon=2,3) population via laser-induced fluorescence detected near 360 nm. The rate coefficients for the vibrational relaxation of O2(X 3sigma(g)-, upsilon=2,3) in collision with O2 are 2.0(-0.4)(+0.6) x 10(-13) cm3 s(-1) and (2.6+/-0.4) x 10(-13) cm3 s(-1), respectively. These rate coefficients agree well with other experimental work but are significantly larger than those produced by various semiclassical theoretical calculations.
authors.affiliation: Molecular Physics Laboratory, SRI International, Menlo Park, California 94025, USA.
authors.forename: Konstantinos S
authors.initials: KS
authors.lastname: Kalogerakis
authors.forename: Richard A
authors.initials: RA
authors.lastname: Copeland
authors.forename: Tom G
authors.initials: TG
authors.lastname: Slanger