Photodissociation dynamics of the singlet and triplet states of the NCN radical
Photodissociation dynamics of the singlet and triplet states of the NCN radical
复制标题
NCN自由基的单线态和三线态的光解离动力学
DOI：
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发表时间：
1999
期刊：
影响因子：
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通讯作者：
D. Neumark
中科院分区：
文献类型：
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作者：
R. Bise;Hyeon Choi;D. Neumark
用快束光碎片平移光谱研究了NCN自由基的光谱和光解离动力学。研究了B 3Σu−←X 3Σg−，c 1Πu←a 1Δg，d 1Δu←a 1Δg跃迁。B 3Σu−和c 1Πu态的主要解离产物为N 2(X 1Σg+)+C(3P)，而d 1Δu态主要解离为N 2(X 1Σg+)+C(1D).当光子能量大于4.9 eV时，在B 3Σu−态下观察到N(4S)+CN(X 2Σ+)解离通道，它占总信号的2 5±10%。在所有的光子能量下，光碎片的平移能量分布呈现出与N_2光碎片的振动激发相对应的分辨级数。分子碎片的旋转分布表明，N_2损失通道的解离途径是弯曲过渡态，而N+CN光碎片是通过线性解离机制产生的。P(Et)分布提供的键离解能分别为2.54±0.030和4.5.
The spectroscopy and photodissociation dynamics of the NCN radical have been investigated by fast beam photofragment translational spectroscopy. The B 3Σu−←X 3Σg−, c 1Πu←a 1Δg, and d 1Δu←a 1Δg transitions were examined. The major dissociation products for the B 3Σu− and c 1Πu states are N2(X 1Σg+)+C(3P), while the d 1Δu state dissociates to N2(X 1Σg+)+C(1D). The dissociation channel, N(4S)+CN(X 2Σ+) is observed for the B 3Σu− state at photon energies greater than 4.9 eV, where it comprises ≈25±10% of the total signal. At all photon energies, the photofragment translational energy distributions show a resolved progression corresponding to the vibrational excitation of the N2 photofragment. The rotational distributions of the molecular fragments suggest that the dissociation pathway for the N2 loss channel involves a bent transition state while the N+CN photofragments are produced via a linear dissociation mechanism. The P(ET) distributions provide bond dissociation energies of 2.54±0.030 and 4.5...