线性BC2nB (n＝1～12)的结构特征和电子光谱的理论研究

应用密度泛函理论, 在B3LYP/6-31G^*水平上优化得到了线性簇合物BC_2nB (n＝1～12, D_(h)的平衡几何构型, 并计算了它们的谐振动频率. 在优化平衡几何构型下, 通过TD-B3LYP/cc-pvDZ和TD-B3LYP/cc-pvTZ计算, 分别得到了n＝1～12和n＝1～7的电子跃迁的垂直激发能和对应的振子强度. 在B3LYP/6-311＋G^*水平上计算得到了簇合物BC_2nB (n＝1～12, D_(h)的电离能. 基于计算结果, 导出了BC_2nB体系电子跃迁能以及第一电离能与体系大小n的解析表达式.

Theoretical Study on Structures and Electronic Spectra of Linear Chain Cluster BC2nB (n=1 ～ 12)

Using density functional theory, the geometries and the vibrational frequencies of linear chain BC_2nB (n＝1～12, D_(h) have been investigated at the B3LYP/6-31G^* level. Time-dependent density functional theory (TD-DFT) has been used to calculate the vertical transition energies and oscillator strengths for transitions of BC_2nB with the cc-pvTZ and cc-pvDZ basis sets. At the B3LYP/6-311＋G^* level, the single-point energies of the clusters have been calculated in order to determine the first ionization energies. On the basis of present calculations, the explicit expressions for the size dependence of the excitation energy, the first adiabatic ionization energies (AIE) and vertical ionization energies (VIE) in linear carbon chains were suggested.