THE EXCITATION-EMISSION MATRIX IN FLUORESCENCE LINE-NARROWING SPECTROSCOPY - A STUDY OF OXAZINE-4-PERCHLORATE IN POLYVINYLBUTYRAL

The full information of the luminescence intensity as a function of excitation and emission wavenumber is contained in the excitation-emission matrix (EEM). An equal intensity contour plot of this EEM allows a convenient two-dimensional presentation of the experimental findings. In FLN spectra the excitation step selects one or more subsets of molecules which are excited into the S1 state. Such spectra depend intrinsically on the excitation wavenumber, and their interpretation is greatly facilitated by study of their contour plots. This technique is applied to oxazine-4-perchlorate in PVB, which shows a very broad inhomogeneous width in comparison to its vibrational spacings and which is therefore difficult to interpret with conventional one-dimensional methods.