【摘要】 以Nd:YAG激光器的二倍频输出光为抽运光,其三倍频输出抽运的光学参量发生/放大器输出光为探测光,利用光学-光学双色双共振多光子离化光谱技术(OODR-MPI),获得了NO2分子在605—675nm探测光波长范围内的多光子离化激发谱.通过对NO2分子离化机理的分析,确定了在此波长区间,NO2分子经1+3+1双共振多光子过程离化,离化通道为NO2(X2A1)hν1→NO2(A2B2)3hν2→NO2(3pσu)hν2→NO2++e.谱线归属结果表明,所得OODR-MPI谱对应于NO2分子3pσu里德伯态的三光子共振吸收,获得了该态的对称伸缩振动频率ω1=(1442.5±25.5)cm-1,弯曲振动频率ω2=(590.5±4.9)cm-1,其带源位于(58331±71)cm-1处,量子亏损值为0.69.更多还原

【Abstract】 The optical-optical double resonance multiphoton ionization （OODR-MPI） technique has been applied to the study of the Rydberg states of nitrogen dioxide. The results show that NO₂ molecule is ionized though a 1+3+1 double resonance multiphoton ionization process in 605—675?nm probe wavelength region. The ionization pathway is: NO₂（X2A₁）hν₁NO₂（A2B₂）3hν₂NO₂（3pσ_u）hν₂NO2₂+e. The OODR-MPI spectrum corresponds to the excitation of NO₂ 3pσ_u Rydberg state by a three photon process. The value ω₁=（1422.5±23.5） cm -1 and ω₂=（590.5±4.9） cm -1 of symmetric stretching and bending vibration frequencies of this Rydberg state are presented. The position of the band origin and the quantum defect of 3pσ_u Rydberg state are obtained to be （58331±71） cm -1 and 0.69, respectively.更多还原