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用DFT-B3LYP方法,在较高基组6-311G**水平下,全优化计算了20种硝基芳烃化合物,从中获得分子最高占用和最低空轨道能(EHOMO和ELUMO)、前线轨道能级差、分子总能量(ET)、硝基净电荷(QNO2)、与硝基相连的苯环碳原子上的净电荷(QC-NO2)、分子偶极矩(μ)和分子体积(V).结合硝基芳烃化合物对沙门氏菌的致变毒性数据(lgNR),由线性回归方法建立QSAR模型,其复相关系数R2=0.916.该模型的预测值与实验值基本吻合.进一步的分析表明,硝基芳烃化合物的毒性主要由ELUMO,QNO2和V决定.苯环上取代基的类型直接影响标题化合物的毒性大小,强吸电子基如硝基会降低ELUMO的大小,使化合物毒性增强;相反,给电子基团氨基的存在则会使化合物的毒性降低.
With the method of DFT-B3LYP, 20 kinds of nitroaromatic compounds were fully optimized and calculated to obtain the highest occupied molecular orbital energy (EHOMO and ELUMO) at the 6-311G ** level. The frontier orbital energy difference , Total molecular energy (ET), net nitro charge (QNO2), net charge (QC-NO2) on the benzene ring carbon atom attached to the nitro group, molecular dipole moment (μ) and molecular volume (V) The mutagenicity data (lgNR) of nitroaromatic compounds against Salmonella were established by the linear regression method, and the complex correlation coefficient R2 = 0.916.The predictive value of this model is in good agreement with the experimental data.Further analysis showed that nitroaromatic hydrocarbon The toxicity of the compound is mainly determined by ELUMO, QNO2 and V. The type of substituents on the benzene ring directly affects the toxicity of the title compound, strong electron-withdrawing groups such as nitro reduce the size of ELUMO and make the compound more toxic; on the contrary, The presence of a cyclomethionine will reduce the toxicity of the compound.