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比较了BP86、PBE、B3LYP、B3PW91、BHand HLYP、PBE0、X3LYP、CAM-B3LYP、TPSS、M06L、M06和M06-2X等12种采用了广义梯度近似(GGA、hybrid GGA、meta-GGA和hybrid meta-GGA)的密度泛函理论(DFT)方法在三个三价铀复合物表征中的应用.研究模型采用铀复合物催化CO2和CS2官能团化反应中的三个中间体(Tp*)2U-η1-CH2Ph(Cpd2),(Tp*)2U-κ2-O2CCH2Ph(Cpd3)和(Tp*)2U-κ2-S2CCH2Ph(Cpd4).研究发现,B3LYP和B3PW91在几何结构和电子结构方面优于其它方法.基于分子轨道理论的MP2方法在Cpd2和Cpd3的表征中给出与DFT方法相近的结果,而在Cpd4的表征中表现出较大的差异.这可能是由于同样是单参考态方法的MP2捕捉到了与DFT方法不同的电子结构.同时,通过对比分别采用小核赝势(5f-in-valence)和大核赝势(5f-in-core)基组处理铀原子的计算结果,发现对测试的模型体系,两种处理方法可获得相近的热力学能量.与以往主要关注高价态锕系复合物的处理方法的评估工作不同,本项工作适应逐渐增加的对低价态锕系分子体系的研究的需求,对12种常用的密度泛函理论方法在低价态锕系复合物研究中的应用进行了评估,期望为处理类似体系的研究工作提供参考.
We compared the generalized gradient approximations (GGA, hybrid GGA, meta-GGA and the hybrid meta-GGA) of BP86, PBE, B3LYP, B3PW91, BHand HLYP, PBE0, X3LYP, CAM-B3LYP, TPSS, M06L, M06 and M06-2X -GGA) in the characterization of three trivalent uranium complexes.Methods The uranium complex was used to catalyze the reaction of three intermediates (Tp *) 2U- (Cpd3) and (Tp *) 2U-κ2-S2CCH2Ph (Cpd4) .The results showed that B3LYP and B3PW91 are superior to other methods in geometry and electronic structure . The MP2 method based on molecular orbital theory gives similar results to the DFT method in the characterization of Cpd2 and Cpd3, but shows a large difference in the characterization of Cpd4, probably due to the MP2 capture that is also a single reference state method To the electronic structure different from that of the DFT method.At the same time, by comparing the calculation results of the uranium atoms with the 5f-in-valence and the 5f-in-core basis sets respectively, Of the model system, the two treatment methods can be similar to the thermodynamic energy with the previous main concern high-priced actinide complex This work adapts to the increasing demand for the study of low-valent actinide molecular systems. The application of 12 commonly used density functional theory methods in the study of low-cost actinide complexes It is expected to provide a reference for the research on similar systems.