A. E. Favorsky Irkutsk Institute of Chemistry, Siberian Branch of the Russian Academy of Sciences, Irkutsk, Russia.
Magn Reson Chem. 2020 Jan;58(1):56-64. doi: 10.1002/mrc.4922. Epub 2019 Jul 31.
A number of computational schemes based on different Density Functional Theory (DFT) functionals in combination with a number of basis sets were tested in the calculation of H and C NMR chemical shifts of strychnine, as a typical representative of the vitally important natural products, and used as a challenging benchmark and a rigorous test for such calculations. It was found that the most accurate computational scheme, as compared with experiment, was PBE0/pcSseg-4//pcseg-3 characterized by a mean absolute error of 0.07 ppm for the range of about 7 ppm for H NMR chemical shifts and that of only 1.13 ppm for C NMR chemical shifts spread over the range of about 150 ppm. For more practical purposes, including investigation of larger molecules from this series, a much more economical computational scheme, PBE0/pcSseg-2//pcseg-2, characterized by almost the same accuracy and much less computational demand, was recommended.
研究了多种基于不同密度泛函理论（DFT）泛函和多种基组的计算方案，用于计算士的宁的 1 H 和 13 C NMR 化学位移，士的宁是生命中重要的天然产物的典型代表，可用作此类计算的挑战性基准和严格测试。结果发现，与实验相比，最准确的计算方案是 PBE0/pcSseg-4//pcseg-3，其 1 H NMR 化学位移范围在约 7 ppm 内的平均绝对误差为 0.07 ppm，13 C NMR 化学位移范围在约 150 ppm 内的平均绝对误差仅为 1.13 ppm。为了更实际的目的，包括对该系列中更大分子的研究，推荐了一种更经济的计算方案 PBE0/pcSseg-2//pcseg-2，其准确性几乎相同，但计算需求大大降低。
