The dynamics of the photofragmentation of hydroxylamine from its lowest excited electronic state,Atilde;thinsp;1Arsquo;, 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 subhyphen;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(Xthinsp;2Pgr;) and NH2(Atilde;thinsp;2A1). NH2(Atilde;) has been detected by its emission spectrum,Atilde;thinsp;2A1rarr;Xtilde;thinsp;2B1, indicating strong vibrational excitation of the ngr;2bending mode. The OH product shows no vibrational excitation, whereas rotational states up toN=20 have been observed. Observation of the product state distributions and of the lang;mgr;sdot;vrang; and lang;vsdot;Jrang; correlations yield a qualitative picture of the upper potential energy surface (PES). Out of the nine coordinates characterizing the normal vibrational modes of H2NOH only the NO distance, the NOH bending angle (responsible for OH rotation), and the NH2bending angle (responsible for NH2bending motion) are involved in the NH2+OH fragmentation channel.
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