Synchronous Scan Luminescence Techniques Monitoring Resonance and Nonresonance Fluorescence in Supersonic Jet Spectrometry Applied to Anthracene Derivatives

A supersonic Jet/fluorescence spectrum Is measured either by monitoring fluorescence at λ_em, = λ_ex (resonant synchronous scan luminescence, R-SSL) or by monitoring total fluorescence but blocking fluorescence at λ_ex = λ_em, (nonresonant synchronous scan luminescence, N-SSL). The R-SSL technique provides a simple spectrum and Is useful for assignment of the chemical species from the database constructed by accumulating the spectral data of 0-0 transitions from the references. On the other hand the N-SSL technique offers a fingerprinting spectrum and is useful for reliable Identification with the standard spectrum. A mixture sample containing anthracene, 1-, 2-, and 9-chtoro-, 2- and 9-methyl-, and 2-ethylanthracene has been measured. Five compounds are readily identified by R-SSL spectrometry using a database of 0-0 transitions. However, two compounds remain unassigned. These two compounds are Identified by careful assignment using the spectral data given by N-SSL spectrometry. The detection limit for anthracene achieved by N-SSL spectrometry Is 7 X 10⁻⁷ M, which Is 2 orders of magnitude better than the value achieved by R-SSL spectrometry. The present method is further applied to solvent-refined coal. Three components, i.e. anthracene and 1- and 2-methyl-anthracene, are detected In this sample.