GAS-PHASE UV SPECTROSCOPY OF ANTHRACENE, XANTHONE, PYRENE, 1-BROMOPYRENE AND 1,2,4-TRICHLOROBENZENE AT ELEVATED-TEMPERATURES

We present quantitative UV-absorption spectra in the wavelength range 200 to 400 nm and the temperature range 150 to 600 degrees C for anthr acene, xanthone, pyrene, 1-bromopyrene and 1,2,4-trichlorobenzene obta ined at 1 atm of air in a slowly flowing gas mixture. As a general tre nd, the spectra shift to the red with increasing temperature and decre ase in peak intensity thus leading to a loss of the characteristic str ucture of the spectrum. The absorption integrated over a particular ba nd generally stays constant or slightly decreases with increasing temp erature. (C) 1997 Elsevier Science S.A.