State-resolved distribution of OH X²Π products arising from electronic quenching of OH A²Σ⁺ by N₂

Dempsey, L.P., Sechler, T.D., Murray, C., Lester, M.I. and Matsika, S. (2009) State-resolved distribution of OH X²Π products arising from electronic quenching of OH A²Σ⁺ by N₂. Journal of Chemical Physics, 130(10), p. 104307. (doi: 10.1063/1.3077027)

Abstract

The nascent OH X ²Π product state distribution arising from collisional quenching of electronically excited OH A ²Σ+ by N₂ has been determined using a pump-probe technique. The majority of OH X ²Π products are observed in their lowest vibrational level, v″ = 0, with significantly less population in v″ = 1. The OH (v″ = 0) products are generated with a substantial degree of rotational excitation, peaking around N″ = 18, with an average rotational energy of ∼ 6500 cm⁻¹. A preference is found for the OH Π(A′) Λ-doublet, indicating some degree of pπ orbital alignment. The branching fraction into OH X ²Π product states demonstrates that nonreactive quenching is the dominant decay pathway for quenching of OH A ²Σ+ by N₂. The topography of the conical intersection region that couples the electronically excited and ground state potential energy surfaces is also examined theoretically. The rotational excitation of the OH X ²Π products and branching fraction are found to be dynamical signatures of nonadiabatic passage through the conical intersection region.

• Item Type: Articles
• Status: Published
• Refereed: Yes
• Glasgow Author(s) Enlighten ID: Murray, Dr Craig
• Authors: Dempsey, L.P., Sechler, T.D., Murray, C., Lester, M.I., and Matsika, S.
• Subjects: Q Science > QD Chemistry
• College/School: College of Science and Engineering > School of Chemistry
• Journal Name: Journal of Chemical Physics
• Journal Abbr.: J. Chem. Phys.
• ISSN: 0021-9606
• ISSN (Online): 1089-7690
• Published Online: 13 March 2009