標題: The absorption and fluorescence spectra of 4-(3-methoxybenzylidene)-2-methyl-oxazalone interpreted by Franck-Condon simulation in various pH solvent environments
作者: Liu, Yu-Hui
Peng, Ya-Jing
Su, Hang
Zhu, Chaoyuan
Lin, Sheng-Hsien
交大名義發表
應用化學系
應用化學系分子科學碩博班
National Chiao Tung University
Department of Applied Chemistry
Institute of Molecular science
公開日期: 21-Aug-2020
摘要: The absorption and fluorescence spectra of 4-(3-methoxybenzylidene)-2-methyl-oxazalone (m-MeOBDI) dissolved in neutral, acidic, and basic solvent environments have been investigated and assigned by using Franck-Condon (FC) simulations at the quantum TDDFT level. Four different structures ofm-MeOBDI in the ground and excited states are optimized and are found to be responsible for the observed absorption and fluorescence spectra. The (absorption) fluorescence ofm-MeOBDI in pure methanol and neutral/basic methanol/water (1/9 vol) mixed solvent is found to arise from the (ground neutral N-I) excited neutral N-I* and cationic C-III* species, respectively. In acidic solvent, the absorption is found to arise from ground acidic C-II species, and the excited divalent cation DC-IV* is found to be formed in its excited state due to the excess H(+)in the solution, and then it emits similar to 560 nm fluorescence. FC simulations have also been employed to confirm our assignments as well as interpret the vibronic band profiles. As expected, the simulated emission spectrum of the divalent cationic species is in good agreement with the experimental observation. Therefore, within the present FC simulation, the observed absorption and fluorescence spectra have been reasonably interpreted and novel fluorescence mechanisms ofm-MeOBDI in various pH solvent environments have been proposed.
URI: http://dx.doi.org/10.1039/d0cp01980a
http://hdl.handle.net/11536/155410
ISSN: 1463-9076
DOI: 10.1039/d0cp01980a
期刊: PHYSICAL CHEMISTRY CHEMICAL PHYSICS
Volume: 22
Issue: 31
起始頁: 17559
結束頁: 17566
Appears in Collections:Articles