Photodissociation dynamics of the phenyl radical via photofragment translational spectroscopy.
Photodissociation dynamics of the phenyl radical via photofragment translational spectroscopy.
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通过光碎片平移光谱研究苯基自由基的光解离动力学。
DOI：
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发表时间：
2010
影响因子：
4.4
通讯作者：
D. Neumark
中科院分区：
文献类型：
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作者：
Bogdan Negru;S. Goncher;Amy Brunsvold;Gabriel M. P. Just;Dayoung Park;D. Neumark
利用光碎片平移光谱研究了苯基自由基C（6）H（5）在248和193 nm处的光解离动力学。在248 nm处，观察到的唯一解离产物来自H原子损失，主要归因于H+o-C（6）H（4）（邻苯炔）。所观察到的平移能量分布与基态表面上的统计衰减一致。在193 nm处，观察到解离为H+C（6）H（4）和C（4）H（3）+C（2）H（2）。C（6）H（4）片段可以是由苯环脱环产生的o-C（6）H（4）或l-C（6）H（4）。C（4）H（3）+C（2）H（2）产物在两个H损失通道中占主导地位。试图通过假设基态动力学来重现所观察到的分支比是不成功的。然而，这些计算假设C（4）H（3）片段是n-C（4）H（3），如果包括较低能量的i-C（4）H（3）+C（2）H（2）通道，则预期会有更好的一致性。
Photofragment translational spectroscopy was used to study the photodissociation dynamics of the phenyl radical C(6)H(5) at 248 and 193 nm. At 248 nm, the only dissociation products observed were from H atom loss, attributed primarily to H+o-C(6)H(4) (ortho-benzyne). The observed translational energy distribution was consistent with statistical decay on the ground state surface. At 193 nm, dissociation to H+C(6)H(4) and C(4)H(3)+C(2)H(2) was observed. The C(6)H(4) fragment can be either o-C(6)H(4) or l-C(6)H(4) resulting from decyclization of the phenyl ring. The C(4)H(3)+C(2)H(2) products dominate over the two H loss channels. Attempts to reproduce the observed branching ratio by assuming ground state dynamics were unsuccessful. However, these calculations assumed that the C(4)H(3) fragment was n-C(4)H(3), and better agreement would be expected if the lower energy i-C(4)H(3)+C(2)H(2) channel were included.