Fluorescence and energy transfer near interfaces: The complete and quantitative description of the Eu+3/mirror systems

Abstract
The classical electromagnetic description of fluorescent emission and energy transfer in the Eu+3/mirror systems is shown to be in quantitative agreement with the results of eight experimental systems studied by the fatty acid monolayer assembly technique. The emitter lifetime measured as a function of distance from the mirror(s) is found to be consistent with an isotropic spatial orientation for the emitter in all cases; furthermore, it is shown to be exclusively so in most of these cases. Both the quantum yield and the radiative lifetime of the luminescent state of the Eu+3 ion are determined by theoretical fits to the data. Whereas the quantum yield spans a range of 0.69–0.86, the radiative lifetime of the electric dipole transition at 612 nm is nearly constant, as required, with a value of 803±29 μsec. Both the quantitative agreement between theory and experiment and the consistency among the eight experimental systems in predicting the radiative lifetime provide a clear demonstration of the utility of the fatty acid monlayer assembly technique as a method of measurement of emission properties of lunimescent systems and of dielectric properties of surfaces.