戊烯自由基阳离子的密度泛函理论研究

DFT Study of the Pentene Radical Cations:Molecular and Hyperfine Structures

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2-C5H10+和1-C5H10+的各种构象进行了几何构型优化,并用B3LYP/6-311G(d,p)进行了频率分析计算.计算预言1-C5H10+具有非平面构型,与以往报导的从头算计算结论相反.在两个自由基阳离子的各种构象的B3LYP几何构型上,进行了B3LYP和UMP2(full)方法的超精细偶合常数计算,得到了比以往更好的结果.

The density function theory (DFT) B3LYP study on the 2-C5H10+ and 1-C5H10+ radical cations has been carried out. The molecular geometries for various conformations of the two 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 1-C5H10+ ion was predicted to have a nonplanar structure, which is in contrast to the previous conclusions based on ab initio calculations. Based on the B3LYP/6-311G(d, p) geometries, the proton isotropic hyperfine coupling constants (HFCCs) were calculated at the B3LYP/6-311G(d, p) and MP2 (full)/6-311G(d, p) levels. The calculated HFCCs results are in good agreement with experiment and more accurate than the previous theoretical results.