X-ray irradiated sodium chloride as an excitation source for the sensitized terbium(III)-specific chemiluminescence of aromatic Tb(III) chelates in aqueous solutions

The viability of X-ray irradiated sodium chloride as the excitation source to generate the radiative 5D4 → 7Fj transitions of chelated terbium(III) is demonstrated. The dissolution of X-ray irradiated sodium chloride in an aqueous solution produces a dynamic solid/solution interface containing hydrated electrons and dissolution-uncovered holes as strong one-electron reducing and oxidizing intermediates, respectively, which provides the energetic basis to initiate the sensitized Tb(UI)-specific extrinsic lyoluminescence of X-ray irradiated sodium chloride by the ligand-oxidation-initiated reductive and/or ligand-reduction-initiated oxidative excitation pathways. Redox luminescence mechanisms of Tb(III) chelates containing phenol, aniline or hydroxybenzophenone derivatives as their chemical energy-accepting aromatic moieties are discussed in detail.