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New [(D-terpyridine)-Ru-(D or A-terpyridine)][4-EtPhCO2]2 complexes (D = electron donor group; A = electron acceptor

Alessia Colombo1, Danika Locatelli, Dominique Roberto

  • 1Dipartimento di Chimica Inorganica, Metallorganica e Analitica Lamberto Malatesta dell'Università degli Studi di Milano, UdR di Milano dell'INSTM, I-20133 Milano, Italy.

Dalton Transactions (Cambridge, England : 2003)
|April 18, 2012
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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