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wskk: 金币+10, 翻译EPI+1, ★★★★★最佳答案, 谢谢你了 2015-04-21 11:16:28
In addition to the trans isomer, photoexcitation of cis-stilbene generates the cyclic product 4a,4b-ihydrophenanthrene in 10% yield.
除了反式异构体，顺势光激励也能生成环状产物4a,4b-二氢菲（产率为10%）。
The yields of the three processes add up to ~1, suggesting that only one pathway may be available for the deactivation excited stilbene.
三个步骤的产率增加到了 ~1，这就标明，其中只有一个方法能够钝化刺激的对称二苯代乙烯。
Trans-stilbene is thermodynamically more stable; however, the barrier to thermal isomerization is significantly larger than that of AB, and the rate of thermal isomerization at room temperature is very slow.
虽然二苯乙烯的热力学稳定性更高，然而，其热异构化的困难比实现AB异构化的困难要大得多，而且在室温环境中，热异构化速率非常慢。
Dynamic simulations and ab initio calculations predict isomerization of stilbene to be dominated by rotation, with some contribution from skeletal deformations.
受骨骼形变的启发，动态仿真和从头计算法预测，对称二苯代乙烯异构将由分子旋转完成。
A crossover point between S1 and S0 states has been located near a torsional angle of 90. Both trans and cis-stilbene must acquire the same conformation prior to S0 ←S1 intersystem crossing; however a small barrier exists on the side of the trans isomer.
经过定位，S1和S0质检的交叉点接近于90度的扭转角。在系统由S1穿越到S0之前，无论顺式和反式异构都必须有同样的构象；其中对于反式异构体，这存在一点小小的困难。
As a result, the S1 state of trans-stilbene has a considerably longer lifetime than that of the cis isomer. Ultrafast timeresolved spectroscopy has revealed S0←S1 relaxation of stilbene to be unimodal.
因此，比起顺式异构体，反式-二苯乙烯的S1状态相当的长。 极速时间分辨光谱法标明，对称二苯代乙烯又S1状态缓冲到S0状态是单向的。 |
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