Chemiluminescent emission spectra of lead, chromium, ruthenium, iron, manganese, rhenium, osmium and tungsten in the reactive flow detector

Spectra have been measured of the chemiluminescent emissions produced by various organometallic compounds passing through the reactive flow detector (RFD). The RFD spectra of osmium, rhenium and tungsten each display a broad continuum from approximately 400 to 800 nm, whose emitting species remain unidentified. The luminescence spectra of lead, chromium, ruthenium, iron and manganese in the reactive flow are each composed of both molecular emission bands, (e.g. metal oxide systems) and atomic emission lines. Compared with the chemiluminescent spectra obtained for these elements in the flame photometric detector (FPD), the atomic emissions in the RFD are relatively more abundant and more intense than the molecular emissions. Additionally, the RFD produces lines of higher energy than the FPD. The highest atomic excitation energy observed in the reactive flow is that of the 280-nm manganese lines (approximately 4.4 eV). This apparent ‘energy limit’ is in excellent agreement with the energy produced by the recombination of hydrogen radicals (4.5 eV), thus implying that this reaction may be the primary source of excitation energy in the reactive flow.