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应用物质结构-性质关系(QSPR)方法研究25种无机含氧酸pK_1与分子描述符之间的定量关系。采用DRAGON5.4软件和HyerChem7.5计算了25种无机含氧酸分子的426种结构类参数和12种量子化学参数。根据偏差权重法筛选出39种结构描述符。采用多元逐步回归分析建立了25种无机含氧酸结构-性质关系,得到最佳方程:pK_1=13.421-4.937X1AV+0.508PCW+1.015S-0.100LUMO+0.398P-3.94~*10~(-7)Et。方程相关系数R为0.995,标准偏差S为0.577。且有F>Fα,表明方程回归效果显著;对回归系数的t检验结果均有Sig<0.05,表明6个参数对pK_1影响显著。“逐一剔除”交叉验证的结果证明模型具有良好的稳定性和较强的预测能力。6个参数物理意义及其对pK_1影响的深入分析表明,其中的S(3Se+Sp-1.75Ss),X1AV(average valence connectivity index chi-1)和PCWte(partial charge weighted topological electronic descriptor)3个参数是影响酸无机含氧强度的关键结构参数。
The quantitative relationship between 25 inorganic oxyacids pK_1 and molecular descriptors was studied by using the method of substance structure - property relationship (QSPR). 426 kinds of structural parameters and 12 kinds of quantum chemical parameters of 25 kinds of inorganic oxoacid molecules were calculated by DRAGON5.4 software and HyerChem7.5. 39 kinds of structure descriptors were screened by deviation weight method. The multivariate stepwise regression analysis established the structure-property relationship of 25 kinds of inorganic oxyacids. The optimal equation was obtained: pK_1 = 13.421-4.937X1AV + 0.508PCW + 1.015S-0.100LUMO + 0.398P-3.94 ~ * 10 -7 ) Et. The equation of correlation coefficient R was 0.995 and the standard deviation S was 0.577. And F> Fα, indicating that the equation regression effect is significant; for the regression coefficient t test results have Sig <0.05, indicating that six parameters have a significant impact on pK_1. The results of cross validation show that the model has good stability and strong predictive ability. The physical meaning of the six parameters and their in-depth analysis of the influence on pK_1 showed that the three parameters of S (3Se + Sp-1.75Ss), X1AV (average valence connectivity index chi-1) and PCWte (partial charge weighted topological electronic descriptor) Is the key structural parameter that affects the strength of acid-inorganic oxygen.