Radiative and predissociative rates for NO A 2Σ+v′=0–5 and D 2Σ+v′=0–3
Radiative and predissociative rates for NO A 2Σ+v′=0–5 and D 2Σ+v′=0–3
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NO A 2Σ+v′=0–5 和 D 2Σ+v′=0–3 的辐射率和预解离率
DOI：
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发表时间：
2000
期刊：
影响因子：
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通讯作者：
D. Crosley
中科院分区：
文献类型：
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作者：
J. Luque;D. Crosley
利用NOA-X(0-5，0)和D-X(0-3，0)带的双光子激光诱导荧光，获得了流动池中A v‘=0-5和D v’=0-3能级的无碰撞寿命。从no A v‘=0到v’=3的振动趋势很小，辐射寿命分别在2 0 5±7~184±8 ns之间，与最近由分支比测量和从头计算得到的结果一致.在NO A 2Σ+和D 2Σ+态下的旋转分辨测量表明，在NOX 2Π态解离极限以上，这些近等能能级的寿命行为截然不同.A 2Σ+v‘=4，5和D 2Σ+v’=0的转动寿命随转动次数基本不变。然而，D 2Σ+v‘=1， 2和3具有很强的转动依赖性，在N’=0和2 0之间减少了近3倍。这些观察结果表明，与基态连续谱的弱耦合是高A 2Σ+能级的最有可能的预解离机制，C 2Π.
Two-photon laser-induced fluorescence of the NO A–X(0–5,0) and D–X(0–3,0) bands is used to obtain collision-free lifetimes of the A v′=0–5 and D v′=0–3 levels in a flow cell. The vibrational trend from NO A v′=0 to v′=3 is small, with radiative lifetimes between 205±7 to 184±8 ns, respectively, in agreement with recent calculations derived from branching ratio measurements and ab initio calculations. Rotationally resolved measurements in the NO A 2Σ+ and D 2Σ+ states reveal very different lifetime behavior for these nearly isoenergetic levels above the NO X 2Π state dissociation limit. The rotational lifetimes of A 2Σ+v′=4,5 and D 2Σ+v′=0 are basically constant with rotation. However, D 2Σ+v′=1, 2, and 3 have a strong rotational dependence, decreasing nearly threefold between N′=0 and 20. These observations suggest weak coupling with the ground-state continuum to be the most likely predissociation mechanism for the high A 2Σ+ levels, and rotational on heterogeneous (gyroscopic) predissociation by the C 2Π...