Theoretical Study of Complex Systems including Transition Metal Elements

我们从理论上研究了含有过渡元的复合系统。主要结果如下：在核内过渡金属配合物的MR-MP2研究中，从d轨道展开的角度明确讨论了金属-金属成键的性质。在反Sandwitch型络合物中，通过考虑d电子数从理论上解释了自旋多重性。对σ-键活化和氧化加成等几个重要的基本步骤进行了理论研究，并通过电子结构计算清楚地展示了它们的电子过程。本文从理论上研究了过渡金属络合物催化反应，这是现代化学研究的重要目标。其中之一是I催化的苯乙炔氰化反应，我们清楚地表明了Ni中心在其中的重要作用。我们还成功地提出了考虑取代基电子结构效应的新模型势--轨道一致有效势(FOC-EP)。用该FOC-EP可以进行大系统的CCSD(T)计算，从而正确地表示键能。

We theoretically investigated compex systems bearing transition etal elements. Important results are summarized below: In the MR-MP2 studies of inuclear transition metal complexes, the metal-metal bonding nature was clearly iscussed in terms of d orbital expansion. In the inverse sandwitch type complexes, spin ultiplicity was theoretically explained by considering d electron numbers. Several mportant elementary steps such as σ-bond activation and oxidative addition were heoretically investigated and their electronic processes were clearly displayed by lectronic structure calculations. Catalytic reactions by transition metal complexes, hich are important target of modern chemistry, were theoretically investigated here. ne of them is i-catalyzed phenyl-cynanation of alkyne, in which we clearly show the mportant role of Ni center. We also succeeded to present new model potential, rontier-Orbital-Consistent Effective Potential (FOC-EP) to incorporate electronic tructure effects of substituent. CCSD(T) calculation of large systems can be carried out ith this FOC-EP, to present bond energy correctly.