Theoretical exploration on excited state behaviors for 2-(1H-benzo[d]imidazole-2-yl)-6-(benzo[d]-thiazol-2-yl)-4-bromophenol in nonpolar and polar solvents
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引用次数: 0
Abstract
Given the potential significance of novel organic fluorophores with potential dual-way proton transfer (PT) reaction channels, in this work we mainly focus on probing into the excited state behaviors for the novel 2-(1H-benzo[d]imidazole-2-yl)-6-(benzo[d]-thiazol-2-yl)-4-bromophenol (BIBTB) fluorophore. Given the two-way PT channels, we firstly check the stable form with hydroxyl points to imidazole and thiazole rings in solvents with different polarities. By twisting dihedral angles (θ1, θ2 and θ3) in the S0 state, we theoretically verify that the A form (hydroxyl points to thiazole ring) should be the most important part in nonpolar and moderately polar solvents, while the D structure (hydroxyl points toward imidazole ring) becomes more important in polar solvents. Mainly focusing on nonpolar cyclohexane (CYC) and polar acetonitrile (ACE) solvents, we compare the geometrical changes and infrared (IR) vibrational spectral behaviors related to hydrogen bonds. The charge reorganization resulting from frontier molecular orbitals (MOs) and predicted hydrogen bonding energies further reflects the excited state intramolecular proton transfer (ESIPT) tendency. By constructing potential energy curves (PECs) and searching for transition state (TS) forms, we confirm and expound the ultrafast ESIPT mechanism for the BIBTB fluorophore.
期刊介绍:
The Journal of the Chinese Chemical Society was founded by The Chemical Society Located in Taipei in 1954, and is the oldest general chemistry journal in Taiwan. It is strictly peer-reviewed and welcomes review articles, full papers, notes and communications written in English. The scope of the Journal of the Chinese Chemical Society covers all major areas of chemistry: organic chemistry, inorganic chemistry, analytical chemistry, biochemistry, physical chemistry, and materials science.