Spectroscopic Studies of Potically-Forbidden Electronically Excited States Produced by Collision of Metastable Excited Atoms.

长寿命激发态的原子是通过放电或电子撞击在气相中产生的，分子的激发态是通过碰撞能量转移有效地形成的。这种方法特别有利于产生传统光激发难以达到的政治禁止激发态。本研究的目的是通过各种光谱测量来研究这些激发态的结构和动力学性质。1985-1986财政年度取得的成果如下：已完成或正在完成22篇论文和38篇口头报告（此外还有40篇论文和20场与本项目密切相关的讲座）。分子与稀有气体亚稳原子碰撞时的解离激发过程：(1)用高分辨率发射光谱研究了氰化物解离激发产生的CN自由基的激发态，明确地确定了<^4(pi)>态的振动-旋转能级。(2) <A^2> <pi>态具有较高的激发振动旋转能级。得到了<^4(pi)>和<A^2> <pi>态的分子常数和RKR势曲线。(3)得到了这些态与<B^2> <(SIGMA)^+>态之间的微扰相互作用常数，以及电子跃迁的依赖关系。对振动量子数的概率进行了分析。(4)研究了CN自由基生成截面和光发射极化随碰撞能量的变化规律，并估计了稀有气体原子碰撞的旋转弛豫速率。(5)用微波光谱法测定了CN（<X^2> <(SIGMA)^+>）高振动态的旋转常数。(6)通过发射光谱分析和动力学计算，研究了与He（<2^3> S）碰撞形成的<H_2O>、<NH_3>、HCl等的双激电子激发态的形成及其解离过程。(7)应用电子能谱法研究了He（<2^3> S）和Ne（<2^ 3P_(0,2)>）原子对石墨或苯覆盖石墨的电子发射过程，研究了固体表面的电子定子和二次电子发射。高激发里德伯稀有气体原子与分子团簇碰撞形成负团簇离子。采用质谱法研究了<CO_2>、<NH_3>、<N_2O> <CCl_4>、吡啶等化合物及其水合簇的电子附着过程。少

Atoms in long-lived excited states are produced in the gas phase by discharge or by electron impact, and excited electronic states of molecules are formed efficiently by means of collisional energy transfer. This method is particularly advantageous for production of potically forbidden excited states, which are not readily accessible by conventional photoexcitation. The purpose of the present study is to investigate the structural and dynamical properties of these excited states by various spectroscopic measurements. The following results have been obtained in the 1985-1986 fiscal years, and 22 papers and 38 oral presentations (besides 40 papers and 20 Talks on subjects closely relates to the present project) have been or are being completed.1. Dissociative excitation processes of molecules in collision with rare-gas metastable atoms:(1) Excited electronic states of CN radical produced by dissociative excitation of cyanides were studied by high-resolution emission spectroscopy, and the … More vibration-rotation levels of the <^4(pi)> state were assigned unambiguously.(2) The higher escited vibration-rotation levels of the <A^2> <pi> State were also assigned. The molecular constants and the RKR potential curves were obtained for the <^4(pi)> and <A^2> <pi> states.(3) Constants of perturbation interactions between these states and the <B^2> <(SIGMA)^+> state were obtained, and the dependences of electronic transition.probability on the vibrational quantum number were analyzed.(4) Cross section for production of the CN radical and the polarization of optical emission were studied as a function of the collision energy, and the rate of rotational relazation by collision of rare gas atoms was also estimated.(5) The rotational constants of higher vibrational states of the CN( <X^2> <(SIGMA)^+> ) state were determined by microwave spectroscopy.(6) Formation of doubly excited electronic excited states of <H_2O> , <NH_3> , HCl, etc. formed by collision with He( <2^3> S) and their dissociation processes were studied by analysis of their emission spectra and by dynamical calculations.(7) Electron spectroscopy was applied to electron emission processes from graphite or that covered with benzene by impact of He( <2^3> S) and Ne( <^3P_(0,2)> atoms, electron stattering and secondary electon emission from solid surface was studied.2. Formation of negative cluster ions by collision of highly excited Rydberg rare-gas atoms with molecular clusters. Mass spectroscopy was used to study electron attachment processes to clusters of <CO_2> , <NH_3> , <N_2O> <CCl_4> , pyridine etc. and some of their hydrated clusters. Less