中文摘要：

采用密度泛函理论方法，计算分析了系列12顶点碳硼烷Ni（Ⅱ）配合物的非线性光学（NLO）性质和电子光谱．结果表明，2个P（CH3）3配体的结构变化对配合物的原子间距离影响较小，Ni（Ⅱ）配合物的极化率随取代基共轭性和空间体积的增加而增大．增强配合物的共轭性及改变P（CH3）3配体结构对二阶NLO系数有明显影响，其中取代基为苯胺的配合物5b的第一超极化率总有效值（届。）最大．分析配合物的电子光谱和相应的分子轨道组成可知，配体内的电荷转移以及配体到金属的电荷转移对二阶NLO系数贡献较大．

英文摘要：

The nonlinear optical（NLO） properties and the electronic spectra of a series of 12-vertex carborane Ni（ Ⅱ ） complexes were investigated with the density functional theory （DFT） method. The results indicate that structural changes of two P（ CH3 ）3 ligands affect slightly the distances between some atoms of complexes, and α values of Ni（ Ⅱ ） complexes increase with the increasing of the conjugation of substituents and spatial volume of the complexes. Enhancing the conjugation and changing the structures of P（ CH3 ） 3 ligands have ob- vious influence on the second-order NLO coefficients, and the first hyperpolarizability（βtot） value of complex 5b which is substituted by aniline group is the largest. Moreover, from the analysis of electronic spectrum and the corresponding molecular orbit composition, it illustrates that the contribution to the second-order NLO coef- ficient mainly comes from intraligand charge transfer and ligand-to-metal charge transfer.