多光子电离谱的微机控制

本文报道了测量多光子电离谱的一整套硬件和软件系统。自行设计实现了将计算机、激光器及Ｂｏｘｃａｒ连接起来的自动控制系统。这一系统大大改善了实验条件，提高了信噪比及仪器的分辨率。所得的实验结果，未曾见报道。     

SYSTEMATIC STUDY OF POLARIZATION OF TWO-PHOTON ABSORPTION IN SYMMETRY ASSIGNMENTS

In this paper, we have systematically analyzed the degenerate and nondegenerate two-photon polarization ratios of various point groups. We present the maximum of symmetry assignments of two-photon transition with the combination of degenerate and nondegenerate two-photon absorption. These results provide the theoretical basis for the experimental assignments.     

EFFECT OF THE LASER TRANSVERSE SPATIAL DISTRIBUTION ON MULTIPHOTON IONIZATION PROCESSES

In this paper, the dependence of the photoionization cross section σ₂, total ion number N_i and the FWHM of photoionization spectral line in resonant multiphoton ionization processes(RMPI) upon the parameter C of the laser transverse spatial distribution has been studied. Considering the effects of spatial coordinate on the resonant multiphoton absorption cross section σ₁, the limited dimension of the laser-molecular interaction volume and threshold of laser intensity for RMPI, we deduce the expression of σ₂ vs the parameter C. We calculated the value of σ₂ for (2+2)PI of benzene by numerical method, and com-pared the result with that obtained by Bruzzeste et al. In additon, we also present the total ion number of photoionization and the FWHM of photoionization spectral line as a function of the parameter C.     

STUDY OF THE POLARIZATION SPECTROSCOPY OF 3p RYDBERG STATES OF m-DIMETHYLBENZENE

A polarization-selected three-photon resonant multiphoton ionization investigation of the 3p Rydberg region of the spectra of m-dimethylbenzene has been conducted. Several vibronic states have been discovered and also assigned for the first time.     

STUDY OF THREE-PHOTON RESONANCE MULTIPHOTON IONIZATION SPECTROSCOPY OF 3p RYDBERG STATES OF m-DIMETHYLBENZENE WITHIN DYE Rh560

In this paper, we studied experimentally the three-photon resonance four-photon ionization spectroscopy of m-dimethylbenzene within dye Rh560. We found several new 3p Rydberg vibronie states and measured their polarization characters. With the help of the measured polarization quantities, we gave the assignment results of these vibronic states: 9b₀¹, A₁; 13₀¹, A₁; 19a₀¹, A₁; 8a₀¹, A₁.     

Na2和Li分子的预解离

最近观测到钠分子和锂分子几个电子态的预解离。现总结了在钠分子和锂分子中观测到的预解离和预解离机制。     

乙苯的三光子共振偏振电离谱

多光子过程的偏振特性可以用来标识电子态及振动结构的对称性.计算了几种简并三光子跃迁张量的理论偏振比值,还测量了乙苯的三光子共振偏振电离谱.经过偏振分析表明,产生跃迁的高电子激发态对称性为A″,并获得了它的振动结构.     

吡啶气相分子的共振多光子电离谱

本工作观测了双光子能量在35180-36002cm^-^1范围内吡啶分子的共振多光子电离谱。对电子跃迁S~1(^1B~1)→S~0(^1A~l)的振动带做了归属, 首次在^1B~1态观察到7个新的振动模。讨论了N原子取代对分子结构及振动模的影响。     

用微扰增强双共振对Na2 2 3Πg和3 3Πg能级进行新观测

Na22^3Пg和3^3Пg态在34860cm^-1(相对基态Te)和3s+3d解离限之间的Ω=0，1，2能级进行了脉冲激光微扰增强双共振探测、观测到两个态之间强烈的相互微扰．给出忽略微扰情况下Ω=0能级的Tv和Bv。     

脉冲激光微扰增强双共振光谱对钠分子43∑g+态的新实验观测

用微扰增强双共振对钠分子43∑g+态33900～35200 cm-1的65个振转能级进行了实验观测.以往用连续激光双共振方法只看到低振动能级,用脉冲激光双共振和检测解离产物的方法只观测到高振动能级.获得的新数据填补了以往数据的空缺.综合v=0～31能级所有数据,拟合出一套分子常数,计算出RKR势能曲线.主要分子常数为:Te=32127.090 cm-1,ωe=121.1099(0.20720)cm-1,Be=0.116287(0.0002300)cm-1,Re=3.551 A.还对J.Chem.Phys.108,7707(1998)中RKR势能曲线的一个错误进行了纠正.