NO2分子在440～495 nm范围内的激光诱导荧光激发谱

以 NdYAG脉冲激光器泵浦的光学参量发生器/放大器作激发光源, 获得了室温、低气压条件下, NO2分子在440～495 nm波长范围内的激光诱导荧光激发谱, 将所得谱线峰归属为NO2由基电子态X2A1态向第二电子激发态B2B1态的跃迁, 利用实验所得峰值波长计算了NO2分子B2B1态的角振动频率ωe. 通过对NO2分子B2B1→X2A1跃迁的荧光时间分辨光谱进行实验研究, 得到15 Pa气压下B2B1(0, 9, 0)振动态的能级寿命τ=49 μs. 测量了荧光寿命随气压的变化关系, 利用曲线拟合得到NO2 B2B1(0, 9, 0)振动态的自发辐射寿命τ0≈55 μs和无辐射跃迁弛豫速率常数. kq=1.2×10-9 cm3 molecule-1s-1.

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).