高能炸药CL-20分子结构的理论模拟方法探究

Study on Methods for Theoretical Modeling the Structure of High Explosive CL-20

采用量子化学方法,在HF/6-31G,DFT-B3LYP/6-31G和MP2/6-31G基组水平下全优化ε-CL-20分子的结构,对ε-CL-20的结构(包括键长、键角、二面角)分析得出B3LYP/6-31G水平下的理论值更接近实验值。采用B3LYP方法,不同基组3-21G,6-31G,6-31++G,6-311++G,6-31++G**水平下全优化ε-CL-20分子,基组选取基本不影响计算结果,表明B3LYP/6-31G基组水平下的计算结果能够满足ε-CL-20的结构优化要求。采用HF、B3LYP、MP2方法不同基组计算ε-CL-20原子的净电荷分布,结果表明充分考虑电子相关性的B3LYP方法计算结果最合理。

Quantum chemistry methods were used to optimize the structure ofε-CL-20 at the level of HF/6-31 G,DFT-B3 LYP/6-31 G and MP2/6-31 G respectively.The structure ofε-CL-20,such as bond length,bond angle,dihedral angle,was analyzed theoretically.The theoretical value at the level of B3 LYP/6-31 G accords with the experimental value.The effects of B3 LYP/3-21 G,B3 LYP/6-31 G,B3 LYP/6-31++G,B3 LYP/6-311++G and B3 LYP/6-31++G**methods on the calculated results ofε-CL-20 are small,which shows that the calculated results at the level of B3 LYP/6-31 G can meet the optimization ofε-CL-20.The atom charges distribution ofε-CL-20 at different levels were calculated quantitatively.The results show that the B3 LYP method in which electron correlation effect has been sufficiently considered is more reasonable.