Aggregation induced emission enhancement and chromism properties of a vinyl bridged naphthalene diimide dimer.

A vinyl bridged 1,4,5,8-Naphthalenetetracarboxylic diimide (NDI) dimer, DNV was synthesized, which exhibits relatively strong Aggregation Induced Emission Enhancement (AIEE) behaviour with absolute quantum yield of 13.6%, as well as wide Aggregation Induced Chromism (AIC) phenomenon (over 100 nm), from green to orange emission. The density functional theory (DFT) and coupled cluster calculations reveal a unique twisted packing mode of DNV in its aggregated state, and mild intermolecular CT between the stacked DNV molecules was also observed. This J -aggregation like molecular arrangement and the net CT might contribute to the long wavelength emission. The bio-imaging capability of DNV is also examined by a living cell experiment. [Display omitted] • A vinyl bridged 1,4,5,8-Naphthalenetetracarboxylic diimide (NDI) dimer, DNV was synthesized and fully characterized. • Aggregation induced strong emission enhancement (AIEE) and large fluorescence chromism (AIC) were realized. • The theoretical calculations revealed a unique twisted packing mode for DNV in its aggregated state (dimer state). • Bio-imaging capability of the DNV material was also examined by living cell experiment. [ABSTRACT FROM AUTHOR]