The Study Of NO High-excited States

The output of the Optical Parameter Generator/Amplifier pumped by Nd:YAG was used to excite NO molecule to study its high-excited electronic states A2Σ+ and E2Σ . Firstly, Resonance-enhanced Multiphoton lonization (REMPI) Spectroscopy of NO was obtained in the range of 420~520nm. Though theoretical analysis, the lines are attributed to the vibrational serials of A2Σ+ and E2Σ . It can be concluded that the ionization process of NO is REMPI process via intermediate A2Σ+(2+2) and E2Σ(3+1) states. At the same time, we get the curve showing the pressure dependence of ionization signal with fixed laser wavelength. Secondly, the Two-Photon Laser Induced Fluorescence Spectroscopy of NO with the exciting wavelength of 452.4nm and 429.6nm was obtained. The fluorescence lines are attributed to the A2Σ(v = 0,1) →X2П transitions. Also we measure the lifetime of fluorescence in the two transitions at different pressures. By theoretical calculation, the collision-free fluorescence radiative lifetime for A2Σ+(v=0,1) and the value of relaxation rate constant are obtained.