精确计算核磁共振屏蔽常数的扩展焦点分析方法

(厦门大学化学化工学院,福建 厦门 361005)

屏蔽常数; 核磁共振; 焦点分析方法

Accurate Calculation of Nuclear Magnetic Resonance Shielding Constants Using Extended Focal Point Analysis Method
WANG Kangli,SUN Meng,WU An'an*

(College of Chemistry and Chemical Engineering,Xiamen University,Xiamen 361005,China)

shielding constant; nuclear magnetic resonance; focal point analysis method

DOI: 10.6043/j.issn.0438-0479.201705027

备注

在焦点分析(FPA-M)方法的基础上,提出了计算屏蔽常数的FPA-M-HF方法.通过外推HF(Hartree-Fock)屏蔽常数至完全基组(complete basis set,CBS)极限,并加上较小基组下CCSD(T)与HF计算屏蔽常数的差值作为高阶相关校正,得到近似CCSD(T)/CBS屏蔽常数.研究表明:在cc-pCVnZ和pcJ-n两个基组下,FAP-M-HF可以精确计算13C,15N,17O 和19F 原子的屏蔽常数,并且超过了CCSD(T)/cc-pV5Z的精确度.

We proposed a FPA-M-HF scheme based on focal point analysis for magnetic(FPA-M)for an accurate calculation of chemical shielding,which added the difference between CCSD(T)and HF to the HF/CBS number to approximate the corresponding CCSD(T)/CBS value.Systematical investigations demonstrated that the FPA-M-HF scheme with a basic set of cc-pCVnZ and pcJ-n performed remarkably well along with the whole set of systems,surpassing,in many aspects,the standard CCSD(T)method with cc-pV5Z.