Three distinct concentration-dependent chromophores of non-traditional intrinsic luminescence: the mechanism and special properties

Abstract Non-traditional intrinsic luminescence (NTIL) have presented many unique properties, which are quite different from traditional fluorescent materials. In this work, using non-aromatic amines, we found three distinct fluorescent peaks at 400 nm, 440 nm and 500 nm, respectively, in a concentration increasing process. The direct proofs obtained from NMR and other techniques suggested that these peaks might originate from different concentration-dependent aggregates. On the other hand, our results well explained the weird phenomena that NTIL systems presented the excitation-dependent fluorescence (EDF) or excitation-independent fluorescence (EIF) in various cases. We proposed a strategy to prepare fluorescent systems with unique property of tunable emission and controllable EDF or EIF, which would be useful in multi-color imaging applications.