Elaborating and regulating ESIPT associated with solvent polarity for the novel 2-(benzo[d]thiazol-2-yl)-4-(9H-diphenylamino-9-yl)phenol fluorophore

Abstract

In light of the potential applications as full-colour organic emitting materials crossing the entire visible spectra, the novel diphenylamino submitted 2-(2’-hydroxyphenyl) benzothiazole derivative 2-(benzo[d]thiazol-2-yl)-4-(9H-diphenylamino-9-yl)phenol (pPhOH) is explored in this work about its excited state behaviours. Solvent-polarity-related photo-induced hydrogen bonding effects of pPhOH indicate nonpolar aprotic solvents largely enhance S₁-state hydrogen bonding interactions. Charge reorganisation stemming from photoexcitation and polarity-dependent energy gap between HOMO and LUMO orbitals further reveals the excited state intramolecular proton transfer (ESIPT) tendency. Insights into potential energy curves (PECs) along ESIPT paths in solvents with different polarities and electronic spectral behaviours of pPhOH as well as its proton-transfer tautomer pPhOH-T, we present solvent polarity could harness the excited state behaviours for pPhOH system.

GRAPHICAL ABSTRACT

KEYWORDS:

• Hydrogen bonding interaction
• solvent polarity
• photo-induced excitation
• charge reorganisation
• ESIPT

Data availability statement

Data are available on request from the corresponding author.

Disclosure statement

No potential conflict of interest was reported by the author(s).

Additional information

Funding

We are grateful to General Program of the Education Department of Liaoning Province [grant number LJKMZ20221473] and Shenyang Normal University doctoral program [grant number BS202206]. The main part of this work was carried out at the Shanxi Supercomputing Center of China, and relevant calculations were performed on TianHe-2.