[The 440-495 nm laser-induced fluorescence excitation spectrum of NO2].

Under the conditions of room temperature and low pressure, laser-induced fluorescence excitation spectrum of NQ2 in the wavelength region of 440-495 nm was obtained by using optical parameter generator (OPG) and amplifier (OPA) as an excitation source. The OPG/OPA was pumped by a Nd:YAG laser. The peaks of the spectrum are attributed to B2B1 <-- X2A1 transition. The angle-vibration frequency of B2B1 electronic state was calculated. The fluorescence lifetime of B2B1 (0, 9, 0) vibration state under the pressure of 15 Pa was also deduced by measuring the fluorescence time decay spectrum of this state. It is about 49 micros. Fitting the curve the fluorescence radiant lifetime versus pressure, the spontaneous radiant lifetimes tau0 and the rate coefficient kq of non-radiant transition relaxation of B2B1 (0, 9, 0) state are deduced. The results are: tau approximately 55 micros and k(q) = 1.2 x 10(-9) cm3 molecule(-1) s(-1).