Repository logo
 

Substantial Intramolecular Charge Transfer Induces Long Emission Wavelengths and Mega Stokes Shifts in 6-Aminocoumarins

Accepted version
Peer-reviewed

Type

Article

Change log

Authors

Cole, JM 
Liu, X 
Xu, Z 

Abstract

Coumarins are deployed in numerous bioimaging and biosensing applications. Among various coumarin derivatives, 6-aminocoumarins attract increasing attention for their red-shifted emissions, mega Stokes shifts, and significant solvatochromism. These spectral characteristics together with weak emission intensities have historically been ascribed to the formation of the twisted intramolecular charge transfer (TICT) state in 6-aminocoumarins. In this work, we demonstrate that it is actually substantial intramolecular charge transfer (ICT) that is responsible for these fluorescent properties. Based on this new understanding, we reanalyzed the sensing mechanism of a 6-aminocouarmin based fluorescent probe and obtained close agreement with experimental data. Our results lead to a deeper understanding of the photophysics of 6-aminocoumarins and will inspire the rational development of novel fluorescent probes.

Description

Keywords

40 Engineering, 34 Chemical Sciences, 4018 Nanotechnology

Journal Title

Journal of Physical Chemistry C

Conference Name

Journal ISSN

1932-7447
1932-7455

Volume Title

121

Publisher

American Chemical Society
Sponsorship
Royal Commission for the Exhibition of 1851 (DF/05/14)
XL: Startup Research Grant (Singapore University of Technology and Design) and SMART Scholar Fellowship (Singapore-MIT Alliance for Research and Technology); JMC: 2014 Design Fellowship (1851 Royal Commission); DOE Office of Science (Office of Basic Energy Sciences; contract No. DE-AC02-06CH11357). ZX: National Natural Science Foundation of China (21422606).