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本文将Pople的闭壳层CNDO/2程序改编成将原子中s,p,d亚层分开处理,并扩展到可计算锆化合物的CNDO/2-TM程序;选取了锆的有关参数;计算了Cp_2ZrX_2(X=F,Cl)分子的电子结构.得到的氯化物分子轨道的能级次序和间隔与光电子能谱相符.计算的偶极矩为5.88D,与实验值相近.计算结果还说明Cp_2ZrX_2是有一定离子性的共价化合物.中心锆原子约呈+1价.金属锆的5s轨道参与茂环的σ键,5p轨道通过移入电子参与茂环σ键,而4d轨道则参与茂环的π键,但成键所占成分不大.Zr-F键的离子性占51％,Zr-Cl键的离子性占44％,Zr-Cp键的共价性在84～93％之间.
In this paper, the closed-shell CNDO / 2 program of Pople was adapted to treat the sub-layers s, p, d of the atoms separately and extended to calculate the CNDO / 2-TM program of zirconium compounds; Cp_2ZrX_2 (X = F, Cl). The order and spacing of the energy levels of the obtained chloride molecular orbitals are in agreement with the photoelectron spectra. The calculated dipole moment is 5.88D, which is close to the experimental value. The calculated results also show that Cp_2ZrX_2 Is a certain ionic covalent compounds center zirconium atoms about +1 price.Metal zirconium 5s orbital participate in the sigma bond of the ring, 5p orbital by moving into the electron to participate in the bond ring mao and 4d orbitals are involved in the ring π bond, but the composition of bond is not large.Zr-F bond ionic accounted for 51%, Zr-Cl bond ionic accounted for 44%, Zr-Cp bond covalent between 84 ~ 93%.