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TiC_3是炼钛熔盐系的常见组分之一.TiCl_3-MgCl_2是重要的载体 Ziegler-Natta 催化剂.在这些体系中都可能存在某种配位型式下的钛(Ⅲ)-氯络离子.因此,用配位场理论对各种配位型式下的钛(Ⅲ)-氯络合离子进行计算,有一定的实际意义. 我们计算用的配位型式模型如图1所示,它们可分为两大类:一类是 TiCl_3在层状(MgCl_2)_n 的折断面上吸附,排成四角对称结构;另一类是 TiCl_3在层状(MgCl_2)_n 的氯离子密排面上吸附,排成三角对称结构.在以下所有的计算中我们取钛-氯间距为2.50.Ti~(3+)和 Cl~-的有效核电荷为 Z_(Ti~(3+))~*=5.8,Z_(Cl)~*=3.6.按照 DSPF 模型,键电荷 q 和它到
TiC_3 is one of the most common components in the molten salt system of titanium. TiCl_3-MgCl_2 is an important carrier of Ziegler-Natta catalyst, and some titanium (Ⅲ) -chloro complex ions may exist in these systems. , And it is of practical significance to calculate the titanium (III) -chloro complex ions under various coordination patterns by using ligand field theory. The model of coordination type we calculated is shown in Figure 1, which can be divided into Two categories: TiCl_3 is adsorbed on the fracture surface of layered (MgCl_2) _n and arranged in a tetragonal symmetry structure; the other is TiCl_3 adsorbed on the surface of MgCl_2 _n close to chloride ion and arranged in Triangular symmetry structure. In all of the following calculations, we take the Titanium-chlorine spacing of 2.50.Ti ~ (3+) and Cl ~ - effective nuclear charge Z_ (Ti ~ (3 +)) * = 5.8, Z_ Cl) ~ * = 3.6. According to the DSPF model, the bond charge q and it go