DIOXYGEN NIR FT-EMISSION (1-DELTA-G-]3-SIGMA-G) AND RAMAN-SPECTRA OF 1,4-DIMETHYLNAPHTHALENE ENDOPEROXIDE - A SOURCE OF SINGLET MOLECULAR-OXYGEN

Singlet molecular oxygen (1O2) monomol light emission (O2, (1)DELTA(g) --> (3)SIGMA-g) generated during the thermodissociation of 1,4-dimethylnaphthalene endoperoxide (1,4-DMNO2) has been directly detected with the use of an FT spectrophotometer equipped with a liquid nitrogen-cooled InGaAs detector. The 1O2 quenching by beta-carotene has been observed. The bimol emission has also been detected by the use of an intensified diode array detector and characterized by enhancement with 1,4-diazabicyclo[2.2.2]octane (DABCO). With a multichannel detector it was possible to obtain the Raman spectrum of 1,4-DMNO2 and to follow its conversion into the parent hydrocarbon 1,4-dimethylnaphthalene (1,4-DMN) by the decrease of the Raman 715-cm-1 peak intensity attributed to the O-O stretching mode.