Theoretical Studies on the Dynamics of Clusters and Excited States

货车德瓦耳斯分子和金属团簇的反应和动力学是近年来实验和理论研究的热点。在本研究项目中，我们用量子化学方法对这些课题中的几个问题进行了研究。其中一些如下。(1)本文用SAC/SAC-CI方法研究了Ar_2，Kr_2，ArF和CsRg（Rg=Ne，Ar，Kr，Cs）等Ven der Waals分子的圆态、激发态和电离态的势能曲线。对于Ar_2，4s和4p Rydberg谱的计算结果与吸收和发射谱的实验结果符合得很好。对观测到的光谱进行了一些新的归属，特别是对来自束缚激发态的激发。对于CsRg体系，SAC-CI势曲线和（诱导）跃迁矩很好地再现了碰撞诱导吸收谱。然后，我们可以澄清详细的电子过程中所观察到的碰撞诱导吸收光谱。(2)的 ...更多信息 指数生成波函数（EGWF）方法是SAC方法的推广。作为SAC-CI方法的推广，提出了应用于EGWF方法的激励器方法。这些方法应用于C_2、CO、HF等分子的基态、激发态、电离态和阴离子态，在正常距离和伸长距离上与完全CI（精确）解符合得很好。结果表明，我们已经准备了基态，激发态，电离态和阴离子态的理论，它适用于任何状态与任意的核配置。该方法也被证明是强大的多电子激发和电离过程。(3)本文用Ag_xO_2（x = 2和4）的DAM模型对氧分子在银表面的化学吸附进行了理论研究。将DAM方法与SAC CI方法相结合，研究了低表面态的电子关联和电子从体金属的转移。对于化学吸附，电子从本体金属转移到调节器和静电图像力是重要的。它们不能用传统的集群模型来处理，而是由DAM来处理。Ag_2O_2^-和Ag_4O_2^-吸附团簇的三个低能级^2A_1、^2A_2和^2B_1参与了化学吸附过程。在分子吸附态中，^2A_1态归属于过氧化物（O_2^<2->）物种，^2A_2和^2B_1态归属于超氧化物（O_2^-）物种。0-0伸缩频率与实验值符合得很好。在Ag_4O_2^-的势能曲线中，对于^2A_1态，得到了与解离吸附态对应的另一个势能极小值。分子吸附和解离吸附的能量学与实验结果符合较好。少

Reactions and dynamics of van der Waals molecules and metal clusters are topics of recent experimental and theoretical studies. In this research project, we have studied several subjects of these topics by quantumchemical methods. Some of them are as follows.(1) Potential energy curves of the round, excited, and ionized states of the Ven der Waals molecules such as Ar_2, Kr_2, ArF, and CsRg (Rg=Ne, Ar, Kr, Xe) are studied by the SAC/SAC-CI method. For Ar_2, the results for the 4s, and 4p Rydberg stated compare very well with the experimental results of the absorption and emission spectra. Some new assignments of the observed spectra are given, particularly for the excitations from the bound excited states. For the CsRg system, the SAC-CI potential curves and the (induced) transition moments have reproduced well the observed collision induced absorption spectra. We could then clarify the detailed electronic processes included in the observed collision induced absorption spectra.(2) The … More Exponentially Generated Wave Function (EGWF) method is proposed as a generalization of the SAC method. The excitator method applied to the EGWF method is proposed as a generalization of the SAC-CI method. These methods are applied to the various ground, excited, ionized, and anion states of C_2, CO, HF, etc at normal and elongated distances with very good agreement with the full CI (exact) solutions. The result implies that we have prepared the theory for the ground, excited, ionized, and anion states which is applicable for any states with arbitrary nuclear configurations. The method has also been shown to be powerful for multi-electron excitation and ionization processes.(3) Chemisorption of an oxygen molecule on a silver surface is studied theoretically with the use of the Dipped Adjuster Model (DAM) for Ag_xO_2 with x = 2 and 4. Electron correlation in low-lying surface states and electron transfer from bulk metal are described by combining DAM with the symmetry-adapted cluster (SAC) CI method. For chemisorption, electron transfer from the bulk metal to the Adjuster and the electrostatic image force are important. They cannot be treated by the conventional cluster model, but are dealt with by the DAM. Three lowlying states, ^2A_1, ^2A_2, and ^2B_1 of the adclusters of Ag_2O_2^- and Ag_4O_2^- are involved in the chemisorption process. In the molecular adsorption state, the ^2A_1 state is assigned to peroxide (O_2^<2->) species and the ^2A_2 and ^2B_1 states to superoxide (O_2^-) species. The 0-0 stretching frequencies are in good agreement with the experimental values. In the potential energy curves of Ag_4O_2^-, another potential minimum corresponding to th e dissociative adsorption state is obtained for the ^2A_1 state. The ener-getics of the molecular and dissociative adsorptions show reasonable agreement with experiments. Less