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Photoinduced anisotropy and polarization holography in a stilbene-containing fluorinated polyimide

Tingchao He1, Changshun Wang, Xu Pan

  • 1Department of Physics, Shanghai Jiao Tong University, Shanghai, China.

Optics Letters
|March 3, 2009
PubMed

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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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