摘要
通过对179个有机化合物C—H,N—H,O—H键离解能的理论计算,系统评估了高精度组合从头算方法(ONIOM-G3B3)和密度泛函理论方法(B3LYP)在预测键离解能上的可靠性.研究发现ONIOM-G3B3方法可以准确预测各类有机化合物的键解离能,精度达到5.9 kJ/mol.运用ONIOM-G3B3方法成功预测了两类重要的天然抗氧化剂维生素E族和茶多酚族的键解离能,并进一步讨论了抗氧化活性、自由基清除机理及其构效关系.
Composite ab initio method （ONIOM-G3B3） and density functional theory （B3LYP） were evaluated against 179 experimental C-H, O-H and N-H bond dissociation enthalpies of diverse organic molecules to verify their performance. It was found that the ONIOM-G3B3 predictions were in good agreement with the experimental values for these three types of bond dissociation enthalpies, and the accuracy was about 5.9 kJ/mol. Finally, armed with this powerful tool two interesting classes of natural antioxidants including vitamin E and catechins in tea were studied. Discussions were made about the antioxidant activity, radical scavenge mechanism and structure-activity relationships.
出处
《化学学报》
SCIE
CAS
CSCD
北大核心
2007年第13期1243-1252,共10页
Acta Chimica Sinica
基金
国家自然科学基金(Nos.20472079
20602034)资助项目
