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Indexed by:期刊论文

Date of Publication:2014-02-01

Journal:CHINESE JOURNAL OF CHEMICAL PHYSICS

Included Journals:SCIE、Scopus

Volume:27

Issue:1

Page Number:51-56

ISSN No.:1674-0068

Key Words:Excited state intramolecular proton transfer; Intramolecular charge transfer; Time-dependent density functional theory; Dark state; Baicalein

Abstract:The excited state intramolecular proton transfer (ESIPT) coupled charge transfer of baicalein has been investigated using steady-state spectroscopic experiment and quantum chemistry calculations. The absence of the absorption peak from S-1 excited state both in the experimental and calculated absorption spectra indicates that S-1 is a dark state. The dark excited state S-1 results in the very weak fluorescence of solid baicalein in the experiment. The frontier molecular orbital and the charge difference densities of baicalein show clearly that the S-1 state is a charge-transfer state whereas the S-2 state is a locally excited state. The only one stationary point on the potential energy profile of excited state suggests that the ESIPT reaction of baicalein is a barrierless process.