Ab initio insights into the mechanism of excited-state intramolecular proton transfer triggered by the second excited singlet state of a fluorescent dye: an anti-Kasha behavior. (7th May 2019)

• Record Type: Journal Article
• Authors: Yuan, Huijuan; Guo, Xugeng; Zhang, Jinglai
• Is Part Of: Materials chemistry frontiers. Volume 3:Number 6(2019)
• Page Start: 1225
• Page End: 1230
• Publication Date: 2019-05-07
• Subjects: Materials science -- Periodicals; Chemistry -- Periodicals; 540
• DOI: 10.1039/c9qm00179d
• Languages: English
• ISSNs: 2052-1529

Abstract

Abstract : An excited-state intramolecular proton transfer (ESIPT) reaction triggered by the second excited singlet S2 state is found by ab initio calculations to be an ultrafast process for a novel fluorophore. Abstract : An excited-state intramolecular proton transfer (ESIPT) reaction triggered by the second excited singlet S2 state is found by sophisticated ab initio calculations to be an ultrafast process for a novel fluorescent dye of 2-((5-(3-hydroxy-4-oxo-4 H -chromen-2-yl)thiophen-2-yl)methylene)malononitrile, 3-HTC-DiCN, which can thoroughly compete with internal conversion from the S2 state to the lowest S1 state, thus leading to the remarkable enhancement of fluorescence quantum yield arising from the proton-transfer tautomer emission as well as the corresponding decrease of the normal emission quantum yield. This is in apparent discrepancy to Kasha's rule.