ELECTRONIC STATES AT SOLID SURFACES AND DYNAMICS OF ELECTRON TRANSFER

我们准备了几种类型的电子态计算方法，如MO、赝势、LCAO和CI方法，用于研究固体表面的电子态，特别是对与电子转移有关的动力学过程的实际应用。尽管我们还有许多需要进一步考虑的地方，但我们将这些程序应用于以下体系的简化版本：1)对于PF_3/Ni(L11)体系，我们考察了PSD中Berry相的影响以及位于Ni(111)表面相邻距离的两个PP_3分子的旋转态。我们发现了一个极小的势垒旋转高度，这表明势垒高度主要是由衬底Ni引起的。我们分别计算了表现出近乎简并的全自旋态的Ni团簇，发现确定基态是困难的。为了澄清这一点，我们现在正在进行CI计算。2)我们对具有固定(平行)几何构型的H_2/Al进行了赝势计算，计算了H_2表面距离的函数，以处理吸附和解离等动力学过程。我们发现了与分子吸附和解离化学吸附相对应的两个势能极小值。我们现在要通过去除分子几何的限制来获得完整的势能曲线。3)作为时间演化方法的应用，我们对含2个电子的原子和离子进行了数值计算，得到了与实验一致的结果。同时，我们发展了介观体系介电函数的数值计算方法。4)为了研究电流在STM针尖分子操纵中的作用，我们建立了留下分子内振动的电流的非弹性散射分量。我们用LCAO方法得到的电子态定性地解释了实验结果。

We prepared several types of electronic state calculations such as MO, pseudo-potential, LCAO, and CI methods, for investigating electronic states at solid surfaces with particular attention for practical applications to dynamical processes related to electron transfer. Although we still have many points to be considered further, we applied those codes to simplified version for the following systems : 1) For PF_3/Ni (l11), we look at the effect of Berry phase in PSD and the rotational states of 2 PP_3 molecules located at the next neighbor distance of Ni(111)surface. We found an extremely small barrier height of rotation, which indicates that the potential height is mostly due to the substrate Ni. We calculated separately the Ni clusters, which show nearly degenerate total-spin states and found difficulty of determining the ground state. To clarify this point we are now making the CI calculations. 2)We made the pseudo-potential calculations on the H_2/Al with a fixed (parallel) geometry as a function of H_2-surface distance to deal with the dynamical processes, such as sorption and dissociation. We found 2 potential minima corresponding to the molecular adsorption and dissociative chemisorption. We are now to obtain the full potential curves by removing the constraints of molecular geometry. 3)As an application of the method of time evolution, we made numerical calculations of atoms and ions with 2 electrons and obtained good agreement to experimental results. Also we developed numerical method of obtaining the dielectric functions of mesoscopic systems. 4)To study effects of electric current in molecule manipulations with STM tip, we formulated the inelastically scattered component of the current leaving intramolecular vibrations behind. We showed that our formulation explain experimental results qualitatively with using electronic states obtained by t.he LCAO method.