A scheme that explicitly contains electrostatic,polarization,and dispersion interactions to rapidly simulate anion-rr interactions is proposed and assessed by structural and energetic comparison with those produced via the complete basis set limit of the coupled-cluster singles and doubles plus perturbative triples [CCSD(T)/CBS] method for a set of X-…C6H6 nRn complexes where X-=F,Cl-,Br and R =CN,F.We use the chemical bonds C≡N,C-F,and C-H of the substituted benzenes as bond dipoles.The electrostatic interactions are estimated by calculating the interactions between the charge of the anion and the bond dipole moments of the substituted benzene.The polarization interactions are described according to the variation of the magnitudes of the bond dipole moments with the local environment.The parameters needed are produced by fitting the high-quality CCSD(T)/CBS potential energy curves.Calculation results show that our scheme produces equilibrium intermolecular distances with a root-mean-square deviation of 0.004 nm and interaction energies with a root-mean-square deviation of 2.81 kJ· mol-1 compared with the CCSD(T)/CBS results.The calculation results also show that our scheme reproduces the CCSD(T)/CBS potential energy curves well.These comparisons indicate the scheme proposed here is accurate and efficient,suggesting it may be a helpful tool to design and simulate relevant molecular materials.%本文提出了一种可快速计算Anion-π作用强度的方法.该方法包含静电、极化和范德华作用.我们将取代苯的C≡N、C-F和C-H化学键作为键偶极,通过阴离子和取代苯的键偶极间相互作用来计算静电作用,根据键偶极大小随着环境变化而改变来计算极化作用.文中所需参数由模拟CCSD(T)/CBS势能曲线而确定.将本文方法应用于一系列卤素阴离子和取代苯间的Anion-π相互作用的快速计算,并与CCSD(T)/CBS方法的计算结果进行了比较.计算结果表明,本文方法得到的势能曲线与CCSD(T)/CBS势能曲线符合很好;与CCSD(T)/CBS方法的计算结果比较,本文方法预测平衡分子间距离均方根偏差为0.004 nm,相互作用能均方根偏差为2.81 kJ·mol-1,说明本文方法合理可靠.本文方法可望在相关分子材料设计模拟领域发挥作用.
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