Mechanism of terbium(III)-enhanced lyoluminescence of x-ray irradiated sodium chloride

Abstract

Dissolution of x-ray irradiated sodium chloride in aqueous solution produces a short-lived dynamic solid/solution interface which is able to raise the hydrated terbium(III) cation to its lowest excited state ( 5D 4) and thus to induce the well-known 5D 4→ 7F-multiplet peak emissions of terbium(III). This contribution points out that the lowest excited state 5D 4 of terbium(III) is attained by an intermolecular energy transfer from a lowest excited singlet state of a solid/solution interface-bound chloride anion which is generated by the recombination of a hydrated electron with the solid/solution interface-bound chlorine atom.