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用分子力学、分子动力学及半经验量子化学方法研究了异丙基膦酸单烷基酯系列稀土萃取剂的空间结构和电子结构．结果表明，烷氧基上的取代基对空间位阻的影响比主碳链大．与稀土原子配位的磷酰氧原子在HOMO中的贡献较大，而LUMO轨道则主要由非配位原子的轨道组成．萃取剂中磷原子、磷酸氧原子以及羟基中氧原子上的电荷分布均随结构的变化呈规律性变化．磷原子和磷酸氧原子上的电荷分布与萃取剂的pKa值呈线性关系．
The molecular structure, electronic structure and molecular structure of the monoalkyl alkyl isopropylphosphonates were studied by molecular mechanics, molecular dynamics and semi-empirical quantum chemical methods. The results show that the substituents on the alkoxy groups have greater steric hindrance than the main carbon chain. Phosphatogen atoms coordinated with rare earth atoms contribute more to HOMO, whereas LUMO orbitals mainly consist of orbitals of noncoordinating atoms. The charge distributions of phosphorus atom, oxygen atom of phosphoric acid and oxygen atom in hydroxyl group all change regularly with the change of structure. The charge distributions on phosphorus atoms and oxygen atoms of phosphoric acid have a linear relationship with the pKa value of extractant.