title: OH produced from o-nitrophenol photolysis: a combined experimental and theoretical investigation.
abstract: Photodissociation dynamics of o-nitrophenol in the gas phase at different photolysis wavelengths (361-390 nm) is investigated, and the nascent OH radical is observed by the single-photon laser-induced fluorescence technique. At all the photolysis wavelengths, the OH radicals are formed in vibrationally cold state (upsilon(")=0) and have similar rotational state distributions. The average rotational temperature for all the photolysis wavelengths is approximately 970+/-120 K, corresponding to a rotational energy of 1.9+/-0.2 kcal mol(-1). The spin orbit and Lambda-doublet states of the OH fragments formed in the dissociation are measured to have nonstatistical distributions. To get an insight into the dissociative mechanism leading to OH formation in the photolysis of o-nitrophenol, the potential energy surfaces of the OH-forming channels are mapped by ab initio theoretical calculations. According to both experimental and theoretical results, a possible mechanism for OH formation is proposed.
authors: State Key Laboratory of Molecular Reaction Dynamics, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Dalian 116023, China.
authors: Shi-Bo
authors: SB
authors: Cheng
authors: Can-Hua
authors: CH
authors: Zhou
authors: Hong-Ming
authors: HM
authors: Yin
authors: Ju-Long
authors: JL
authors: Sun
authors: Ke-Li
authors: KL
authors: Han
mesh_terms: D003198:Computer Simulation; D017665:Hydroxyl Radical / Q000138:chemical synthesis* / Q000737:chemistry; D007834:Lasers; D009596:Nitrophenols / Q000737:chemistry*; D010782:Photolysis; D011789:Quantum Theory; D012399:Rotation; D013050:Spectrometry, Fluorescence; D013499:Surface Properties; D013696:Temperature; D014732:Vibration
chemical_list: D009596:Nitrophenols; D017665:Hydroxyl Radical; C045573:2-nitrophenol