Photodissociation dynamics of NH2OH from the first absorption band

The dynamics of the photofragmentation of hydroxylamine from its lowest excited electronic state, A 1A’, have been investigated. The main dissociation channel leads to H+H+HNO with a quantum efficiency of 1.7 for hydrogen atoms. The H atoms have been analyzed by laser induced fluorescence using a frequency tripled dye laser with sub‐Doppler resolution. A sequential decay process is proposed where the first ejected H fragment leaves a highly vibrationally excited intermediate which dissociates after intramolecular vibrational redistribution into H+HNO. Another photodissociation channel leads to OH(X 2Π) and NH2(A 2A1). NH2(A) has been detected by its emission spectrum, A 2A1→X 2B1, indicating strong vibrational excitation of the ν2 bending mode. The OH product shows no vibrational excitation, whereas rotational states up to N=20 have been observed. Observation of the product state distributions and of the 〈μ⋅v〉 and 〈v⋅J〉 correlations yield a qualitative picture of the upper potential energy surface (P...

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