Sc_(3)C_(2)@C_(80)与[12]CPP纳米环之间非共价相互作用的理论研究

Theoretical Exploration of Noncovalent Interactions Between Sc_(3)C_(2)@C_(80) and [12] Cycloparaphenylene Nanoring

金属富勒烯嵌套于纳米环内形成主客体系,二者产生的主客体作用可诱导内部金属团簇的取向,影响分子的电子结构等性质.本文基于密度泛函理论(DFT)计算,对碳纳米环[12]CPP(CPP=环苯撑,主体分子)与金属富勒烯Sc_(3)C_(2)@C_(80)(客体分子)形成的主客体配合物的结构和性质进行了研究.计算结果表明,在最稳定构型中,[12]CPP呈现椭圆形, Sc_(3)C_(2)@C_(80)与[12]CPP的质心不再重合. Sc_(3)C_(2)@C_(80)在[12]CPP内旋转对构型总体能量影响仅为13.51 kJ/mol.[12]CPP向Sc_(3)C_(2)@C_(80)转移了0.03 e,主客体分子之间存在弱相互作用.对二者相互作用的分析结果表明,色散作用在弱相互作用中占主导地位.

The encapsulations of fullerenes by carbon-nanorings are of great interest because of their unique molecular structure and special properties.The host-guest interaction between them can induce the orientation of metal ions and change the molecular electronic structure.However,due to experimental difficulties,there are many opportunities for the computational efforts to deeply research the intrinsic features of π-π noncovalent interactions of the fullerene ■cycloparaphenylene(CPP)carbon-nanoring host-guest systems.Herein,the molecular carbon nanoring of[12]cycloparaphenylene was used to hoop the C-based metallofullerene Sc_(3)C_(2)@C_(80).The structures and properties of the host-guest complex were systematically characterized by density functional theory(DFT)calculations.It was found that[12]CPP is deformed because of the asymmetrical attraction of[12]CPP to Sc_(3)C_(2)@C_(80).The centroids of Sc_(3)C_(2)@C_(80) and[12]CPP no longer coincide.The results also showed that the influence of rotation of Sc_(3)C_(2)@C_(80) in[12]CPP on the overall energy of the configuration is only 13.51 kJ/mol.Moreover,charge population analysis shows that 0.03 electrons are transferred from[12]CPP to Sc_(3)C_(2)@C_(80) during the formation of Sc_(3)C_(2)@C_(80)■[12]CPP.Weak interactions between host-guest systems can be further partitioned with the help of energy decomposition analysis(EDA).EDA analysis shows that dispersion is dominant.These results provide theoretical support for the study of host-guest systems based on metallofullerenes.