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本文应用量子化学MINDO/3法对PAR分子结构进行计算,指出: (1)PAR分子中存在π_(16)~(18)共轭体系,在各种PAR分子构型中,仅反式偶氮型能与金属离子形成三合配位。 (2)在两种反式构型中,根据计算的总能量,Ⅰ型较Ⅱ型稳定,而计算的偶极矩Ⅰ型小于Ⅱ型,且Ⅰ型电离能比Ⅱ型大。 (3)计算得到的HOMO正是主要由偶氮上的孤对电子对形成的离域分子轨道。从理论上说明了为什么此孤对电子对是配位电子。 (4)按照广义微扰理论的观点,指出L_m~(3+)与PAR分子作用主要是电荷控制反应,因而配位在Ⅰ型的N_(11)上。而Pd~(2+)与PAR分子作用则主要是轨道控制反应,因而它与Ⅱ型配位在N_(12)原子上。
In this paper, the molecular structure of PAR was calculated by MINDO / 3 method. The results showed that: (1) π_ (16) ~ (18) conjugates existed in PAR molecule. Type and metal ions to form triple coordination. (2) In the two trans configurations, type I is more stable than type II, and the calculated dipole moment I is smaller than type II, and type I is larger than type II, according to the calculated total energy. (3) The calculated HOMO is the delocalized molecular orbital formed mainly by the lone pair of electrons on azo. Theoretically shows why the lone pair is the coordination electron. (4) According to the generalized perturbation theory, it is pointed out that the interaction between L_m ~ (3+) and PAR molecules is dominated by the charge control reaction and thus coordinated to type Ⅰ N_ (11). However, Pd ~ (2+) interacts with PAR molecule mainly in orbit control reaction, and thus it is coordinated with type Ⅱ on N 12 atom.