NO分子和氧原子的高分辨离子谱实验研究

Experimental Study of High-Resolution Ion Spectra of NO Molecule and Oxygen Atom

共振增强多光子电离及飞行时间质谱技术是一种具有高分辨率、高灵敏度的光谱研究技术。利用上述技术研究了由激光光解NO2 产物NO与原子O的离子谱,获得了振转态高度分辨的NO(X 2Π,ν″,J″)γ(0,0)γ(0,1)γ(1,1)带的离子谱以及自旋-轨道精细能级分辨的氧原子O(2P3PJ″=2,1,0)离子谱。氧原子O(2P3PJ″=2→3P3PJ′、2P3PJ″=1→3P3PJ′、2P3PJ″=0→3P3PJ′)的离子信号位于紫外电离探测激光的波长分别为225.65 nm,226.04 nm,226.23 nm。实验表明,共振增强多光子电离加飞行时间技术研究原子、分子光谱其灵敏度与分辨率远高于常用的激光感生荧光方法。所得到的NO分子与氧原子的离子谱及它们的离子信号对NO2 分子光解及NO分子与氧原子的电离动力学研究提供了有益的实验信息。

Resonance enhanced multiphoton ionization (REMPI) and time of flight (TOF) mass spectrometer technique is a high-resolution and high-sensitivity spectrum-research method. The vibrotation state resolution ion spectrum of the NO(X2∏,v',J') from NO(A2Σ, v=0,1,J'←X2∏, v'=0,1,J') transition γ(0,0) γ(0,1) γ(1,1) and the spin-orbit fine structure resolved ion spectrum of the oxygen atom from the two-photo transition of O(2P3PJ'&rarr3P 3PJ) are obtained by the laser dissociation NO2 using above method. The O(2P3PJ'=2&rarr3P3PJ', 2P3PJ'=1&rarr3P3PJ, 2P3PJ'=0&rarr3P3PJ) ion signals correspond ultravidet (UV) ionization detection laser wavelength at 225.65 nm, 226.04 nm, 226.23 nm respectively. The experimental result shows, the resolution and sensitivity of REMPI and TOF mass spectrometer technique is higher than that of laser induced fluorescence method (LIP). The obtained ion spectra of NO molecule and oxygen atom are very useful experimental information for research of the NO2 photodissociation and the ionization dynamics of NO molecule and oxygen atom.