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Updated: Jun 4, 2025

Determination of the Photoisomerization Quantum Yield of a Hydrazone Photoswitch
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在2D MoS2-diarylethene混合物中,层数依赖的光交换性

Sewon Park1, Jaehoon Ji1, Srajan Pillai2

  • 1School of Mechanical Engineering, Purdue University, West Lafayette, Indiana 47907, USA. jchoi@purdue.edu.

Nanoscale
|December 19, 2024
PubMed
概括

光色的二甲基乙烯分子调节二硫化物 (MoS) 的特性. 在单层MoS2中观察到的这种层依赖效应,但不是更厚的片,使可光开关的电子设备成为可能.

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Photochemical Electrocyclic Reactions: Stereochemistry

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.
Selection Rules: Photochemical Activation
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Isomerism in Complexes
Isomers are different chemical species that have the same chemical formula.
Transition metal complexes often exist as geometric isomers, in which the same atoms are connected through the same types of bonds but with differences in their orientation in space. Coordination complexes with two different ligands in the cis and trans positions from a ligand of interest form isomers. For example, the octahedral [Co(NH3)4Cl2]+ ion has two isomers (Figure 1) In the cis...
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