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利用脉宽小于5 fs的激光脉冲超快光谱同时研究了RuⅡ(TPP)(CO)的电子弛豫和振动动力学。研究认为,由1Qx(1,0)(π,π*)and1Qx(0,0)(π,π*)产生的信号按1Qx(1,0)(π,π*)→1Qx(0,0)(π,π*)→3(d,π*)→3(π,π*)和1Qx(0,0)(π,π*)→3(d,π*)→3(π,π*)的顺序从高能态衰减到低能态1。Qx(1,0)(π,π*),1Qx(0,0)(π,π*),3(d,π*),和3(π,π*)的电子寿命依次为(230±70)fs,(1 150±260)fs,(2 150±360)fs和极大于4.8 ps3。(d,π*)和3(π,π*)的寿命估计为(2150±360)fs和极大于4.8 ps。计算动态Stokes-shift过程中的能量衰减率,得到了从1Qx(1,0)(π,π*)到1Qx(0,0)(π,π*)的渡越时间为(190±40)fs,表明1Qx(1,0)(π,π*)的寿命与该渡越时间有相对较好的一致性。对频谱图的分析表明,依赖时间变化的振动光谱与自旋态变化有关,自旋态可以通过曲线交叉点或者单态和三重态之间的势能面的圆锥交面从激发单重态中的Franck-Condon态变化到三重态。研究发现,不能简单地使用单重态信号频谱的指数衰减形式和三重态振动信号频谱的指数增长形式来表示这种动态变化。相反,振动频谱的变化伴随着复杂的动态变化。首先,单重态振动频谱发生衰减,然后产生不同于单重态和三重态的新的振动频谱。新的振动频谱增长和衰减后,三重态的振动频谱开始增长。这种动态变化似乎与电子频谱的动态变化不同,将这种明显差异的原因解释为:振动频谱的变化可以敏感地检测处于平衡点和过渡状态或者接近锥形交集状态中的单重态和三重态的结构差异。
The electron relaxation and vibrational kinetics of Ru Ⅱ (TPP) (CO) have been studied simultaneously using laser pulse ultrafast spectroscopy with pulse width less than 5 fs. It is considered that signals generated by 1Qx (1, 0) (π, π *) and 1Qx (0,0) (π, π *) are expressed by 1Qx (1,0) (π, π *) → 1Qx (π, π *) → 3 (d, π *) → 3 (π, π *) and 1Qx (0,0) (π, π *) → 3 *) Decays from the high energy state to the low energy state 1. The electron lifetimes of Qx (1, 0) (π, π *), 1Qx (0,0) (π, π *), 3 (d, π *) and 3 (π, 70) fs, (1 150 ± 260) fs, (2 150 ± 360) fs and maximally 4.8 ps3. The lifetimes of (d, π *) and 3 (π, π *) are estimated to be (2150 ± 360) fs and very much greater than 4.8 ps. The energy decay rate in the dynamic Stokes-shift process was calculated and the transit time from 1Qx (1,0) (π, π *) to 1Qx (0,0) (π, π *) was found to be (190 ± 40) fs, indicating that the lifetime of 1Qx (1,0) (π, π *) is relatively consistent with the transit time. The analysis of the spectrogram shows that the vibrational spectra dependent on time are related to the change of the spin state. The spin state can be obtained from the cross-point of the curve or from the cone interface of the potential energy surface between the singlet state and the triplet state from the singlet state Franck-Condon states change to triplet state. The study found that this dynamic change can not simply be expressed using the exponential decay of the singlet signal spectrum and the exponential increase of the triplet vibration signal spectrum. In contrast, changes in the vibrational spectrum are accompanied by complex dynamics. First, the singlet vibrational spectrum decays, and new vibrational spectra that differ from the singlet and triplet states are generated. After the new vibrational spectrum increases and decays, the vibrational spectrum of the triplet state begins to grow. This dynamic change appears to be different from the dynamic changes in the electronic spectrum. The reason for this apparent discrepancy is explained by the fact that changes in the vibrational spectrum can sensitively detect singlet and triplets at equilibrium or transitional states or near conical intersection Structural differences.