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有效预测La_xM_(1-x-z)R_zMn_yN_(1-y)O_3型新钙钛矿材料的居里温度对于指定居里温度的材料设计至关重要。本工作构建了基于支持向量机的QSPR模型,用以预测La_xM_(1-x-z)R_zMn_yN_(1-y)O_3型钙钛矿材料的居里温度。在13个描述符中筛选出5个描述符来进行建模。建模过程中采用前进法从13个分子描述符中筛选出了5个影响该材料居里温度的主要分子描述符。为了得到优化的建模结果,运用粒子群算法进行了一个参数优化,设置参数ε=0.006,C=6.450,Rbf gamma=1.741。研究结果表明,所建模型的均方根误差RMSE、平均相对误差MRE、计算值与实际值的相关系数R分别为6.82,2.36%和0.991。在留一法交叉验证结果中,均方根误差(RMSE)为20.796,平均相对误差(MRE)为7.35%,计算值与实际值的相关系数(R)为0.92。利用随机抽取的外部测试集样本对所建支持向量回归模型进行检验,得到的居里温度预报的平均相对误差为2.36%。因此,支持向量回归模型能有效预测La_xM_(1-x-z)R_zMn_yN_(1-y)O_3型钙钛矿材料的居里温度,有望在指定居里温度的材料设计研究工作中得到进一步应用。
Effectively predicting the Curie temperature of La_xM_ (1-x-z) R_zMn_yN_ (1-y) O_3 new perovskite materials is crucial for the material design of the given Curie temperature. In this work, a QSPR model based on support vector machines was constructed to predict the Curie temperature of La_xM_ (1-x-z) R_zMn_yN_ (1-y) O_3 perovskite materials. Five descriptors were screened out of 13 descriptors for modeling. In the modeling process, five major molecular descriptors that affect the Curie temperature of the material were screened from 13 molecular descriptors using the forward method. In order to obtain the optimized modeling results, a parameter optimization is carried out by using Particle Swarm Optimization. The parameters ε = 0.006, C = 6.450, Rbf gamma = 1.741 are set. The results show that the root mean square error (RMSE) and the average relative error (MRE) of the model are respectively 6.82, 2.36% and 0.991 for the calculated and actual values. The RMSE was 20.796 and the average relative error (MRE) was 7.35%. The correlation coefficient (R) between calculated and actual values was 0.92. The support vector regression model was tested using a random sample of external test samples. The average relative error of the predicted Curie temperature was 2.36%. Therefore, the support vector regression model can effectively predict the Curie temperature of La_xM_ (1-x-z) R_zMn_yN_ (1-y) O_3 type perovskite material and is expected to be further applied in the design of materials with specified Curie temperature.