液体核磁共振 HSQC 实验的量子化学计算与模拟

核磁共振（NMR）异核单量子相干（HSQC）实验因具有较高的灵敏度和分辨率而被广泛用于液体大分子化合物的结构鉴定和研究．然而由于HSQC脉冲的复杂性，需要严格控制实验参数和实验条件才能得到高质量的谱图．本文基于量子力学原理对HSQC实验进行数学建模，通过理论推导、数值计算求解自旋1/2的IS双核体系在每个脉冲节点作用后的密度矩阵，然后结合二维NMR信号采样方法，使用计算机程序完成了该体系HSQC谱图的模拟，同时，还实现了乙醇分子的HSQC谱图模拟． HSQC实验的成功模拟基于对复杂演化过程的精确计算，可用于预测谱图以及实验参数改变对NMR谱图的影响，指导高质量HSQC实验谱图的采集．

Quantum Chemical Calculation and Simulation of HSQC Experiments in Liquid-State NMR

Due to its high sensitivity and resolution,the heteronuclear single quantum correlation(HSQC)experiment is widely used for nuclear magnetic resonance(NMR)-based structural elucidation and research on solution state macromolecules.However,optimizing instrument settings and experimental parameters in the HSQC experiments can be troublesome due to the complexity of the pulse sequence.In this work,we simulated HSQC spectra based on a quantum model.Through theoretical derivation and numerical calculation,the density matrix evolution of a two-spin ensemble with spin 1/2(IS)was obtained after each pulse,which was then combined with the two-dimensional NMR sampling method to achieve spectral simulation of the HSQC experiment.For validation,the HSQC spectrum of ethanol was simulated.The simulation of HSQC experiment will be beneficial for spectrum prediction,and guide HSQC experimental setup to improve spectral quality.