[5] :,X线

Hui Yang1, Guofeng Chen1, Ran Zhang1

  • 1College of Chemistry and Materials Science, Key Laboratory of Chemical Biology of Hebei Province, Hebei University, Baoding 071002, P. R. China. chenguofeng@hbu.cn.

Nanoscale
|February 20, 2024
PubMed
概括

合成了两种新的基于氨酸的 [5] 烯衍生物,它们显示出绿色光. 他们的纳米线形式显著改善了光电转换,突出了有序纳米结构对设备性能的重要性.

相关概念视频

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The absorption of UV–visible light by conjugated systems causes the promotion of an electron from the ground state to the excited state. Consequently, photochemical electrocyclic reactions proceed via the excited-state HOMO rather than the ground-state HOMO. Since the ground- and excited-state HOMOs have different symmetries, the stereochemical outcome of electrocyclic reactions depends on the mode of activation; i.e., thermal or photochemical.
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Cycloheptatriene is a neutral monocyclic unsaturated hydrocarbon that consists of an odd number of carbon atoms and an intervening sp3 carbon in the ring. The three double bonds in the ring correspond to 6 π electrons, which is a Huckel number, and therefore satisfies the criteria of 4n + 2 π electrons. However, the intervening sp3 carbon disrupts the continuous overlap of p orbitals. As a result, cycloheptatriene is not aromatic.
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