Non-radiative transitions as Förster's energy transfer to solvent vibrations

Abstract

New experimental evidence is given to the approach suggested by the authors to non-radiative transitions in rare earth and transition metal ions as radiationless energy transfer from ion to ligand and solvent molecule vibrations. Using non-radiative transitions in Yb 3+ as an example the participation of combinations of vibrations in the electronic energy dissipation was investigated. Dy 3+ in solutions was used to show the role of anharmonicity in non-radiative transitions. It was proved that the semi-empirical calculations of non-radiative transition rates by Förster's formula gave also good results for Mn 2+ ions luminescence which is an example of “strong” vibronic interaction. The suggested approach permits to explain the anomalous low probability of the 5D 1− 5D 0 non-radiative transition in the Eu 3+ ion.