四苯硼阴离子电子结构的理论研究

分别应用半经验发子轨道理论的AM1方法和在HF／3－21G水平上的从头算分子轨道法，对四苯硼阴离子的电子结构进行了研究。采用解析梯度技术对四苯硼阴离子的平衡态几何构型进行了全优化，得到了分子轨道、电荷布居、静电势以及红外光谱和紫外光谱等参数，计算结果表明：四苯硼阴离子的静电势分布均匀，其前线轨道能级间隔为12．1398eV，利用组态相互作用法得到的紫外光谱跃迁吸收峰主要位于远紫外区，说明四苯硼离子比较稳定，从头算法得到的红外光谱吸收峰分布与实验结果一致，AM1法得到的红外吸收频率与实验值更接近。

The quantum chemical studies of the electronic structures of tetraphenylborate anion

The electronic structures of tetraphenylborate anion have been studied by semiemprical(AM1) and ab initio SCF MO method at the level of HF/3-21G. The geometry is optimized by the technique of analyzed gradient of energy. The molecular orbital, net charge, electrostatic potential and molecular spectra are calculated. The results show that the tetraphenylborate anion has a homogeneous electrostatic potential and the bandwidth of energy level is 12.139 8 eV between the HOMO and LUMO. Its UV absorption peaks calculated by CI method are mainly appeared in far ultraviolet regions. The IR spectra obtained from HF/3-21G has an accordance distribution with experiment, and from AM1 has a good vibration frequency.