title: A dispersed fluorescence and ab initio investigation of the X2B1 and A2A1 electronic states of the PH2 molecule.
abstract: In this work, the X2B1 and A2A1 electronic states of the phosphino (PH2) free radical have been studied by dispersed fluorescence and ab initio methods. PH2 molecules were produced in a molecular free-jet apparatus by laser vaporizing a silicon rod in the presence of phosphine (PH3) gas diluted in helium. The laser-induced fluorescence, from the excited A2A1 electronic state down to the ground electronic state, was dispersed and analyzed. Ten (upsilon1upsilon2upsilon3) vibrationally excited levels of the ground electronic state, with upsilon1 < or = 2, upsilon2 < or = 6, and upsilon3 = 0, have been observed. Ab initio potential-energy surfaces for the X2B1 and A2A1 electronic states have been calculated at 210 points. These two states correlate with a 2Pi(u) state at linearity and they interact by the Renner-Teller coupling and spin-orbit coupling. Using the ab initio potential-energy surfaces with our RENNER computer program system, the vibronic structure and relative intensities of the A2A1 --> X2B1 emission band system have been calculated in order to corroborate the experimental assignments.
authors.affiliation: Steacie Institute for Molecular Sciences, National Research Council of Canada, Ottawa, Ontario K1A 0R6, Canada. zygmunt.jakubek@nrc.ca
authors.forename: Z J
authors.initials: ZJ
authors.lastname: Jakubek
authors.forename: P R
authors.initials: PR
authors.lastname: Bunker
authors.forename: M
authors.initials: M
authors.lastname: Zachwieja
authors.forename: S G
authors.initials: SG
authors.lastname: Nakhate
authors.forename: B
authors.initials: B
authors.lastname: Simard
authors.forename: S N
authors.initials: SN
authors.lastname: Yurchenko
authors.forename: W
authors.initials: W
authors.lastname: Thiel
authors.forename: Per
authors.initials: P
authors.lastname: Jensen