已烯自由基阳离子的密度泛函理论研究

使用密度泛函理论B3LYP方法和6-31G(d,p),6-31+G(d,p),6-311G(d,p)及6- 311+G(d,p)基组，分别对1-C_6H_(12)~+,2-C_6H_(12)~+和3-C_6H_(12)~+的各种构 象进行了几何构型优化，并在B3LYP/6-311G(d,p)水平上进行了频率分析计算，在 各优化构型上，使用B3LYP和MP2(full)方法进行了超精细结构的计算。计算的3- C_6H_(12)~+的超精细偶合常数比以往的计算结果更好；1-C_6H_(12)~+和2-C_6H_ (12)~+的超精细偶合常数目前尚无实验数据报道，本计算预言了它们的超精细偶合 常数和最稳定构型。

A DFT Study of the Hexene Radical Cations-Molecular and Hyperfine Structures

A DFT B3LYP study on the 1 C 6H + 12 , 2 C 6H + 12 and 3 C 6H + 12 radical cations has been carried out. The molecular geometries for various conformations of the three cations were optimized at the B3LYP/6 31G(d, p), B3LYP/6 31+G(d, p), B3LYP/6 311G(d, p) and B3LYP/6 311+G(d, p) levels, and the frequency analysis calculations were performed at the B3LYP/6 311G(d, p) level. The most stable conformations are predicted for the three cations. Based on the B3LYP/6 311G(d, p) geometries, the proton isotropic hyperfine coupling constants ( hfcc's) were calculated at the B3LYP/6 311G(d, p) and MP2(full)/6 311G(d, p) levels. The calculated hfcc results for 3 C 6H + 12 are in good agreement with experiment and more accurate than the previous theoretical results. No experimental hfcc data are available for either 1 C 6H + 12 or 2 C 6H + 12 . The hfcc's values and the most stable structures for both 1 C 6H + 12 and 2 C 6H + 12 are predicted in the present work.