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用分子轨道法研究了镧－菸酸配合物的电子结构和化学键性质．配合物的ＨＯＭＯ（最高占据分子轨道）主要由Ｃ、Ｏ、Ｎ原子的２ｐ轨道组成；ＬＵＭＯ（最低非占据分子轨道）主要由Ｌａ３＋离子的６ｓ、５ｄ、４ｆ轨道组成．在配位过程中有配体向金属离子的电荷转移．配体共转移１．０１７个电子到金属离子上，与Ｌａ３＋离子带１．９８３个正电荷相符合．Ｌａ—Ｏ键具有一定的共价性，由Ｃ原子、两个Ｏ原子与金属离子形成的共价键有一定的流动性．其中５ｄ轨道对形成Ｌａ—Ｏ配位键贡献最大，４ｆ轨道贡献最小．
The electronic structure and chemical bond properties of lanthanum-nicotinic acid complexes were studied by molecular orbital method. The HOMO (Highest Occupied Molecular Orbital) of the complex mainly consists of 2p orbitals of C, O and N atoms. The LUMO (lowest unoccupied molecular orbital) mainly consists of 6s, 5d and 4f orbitals of La3 + ions. There is a charge transfer from the ligand to the metal ion during the coordination process. Ligands co-transferred 1.017 electrons to metal ions, which was consistent with 1.983 positive charges of La3 + ions. La-O bond has a certain degree of covalence, the C atom, two O atoms and metal ions formed covalent bond has a certain mobility. Among them, the 5d orbitals contributed the most to La-O coordination bond and the 4f orbitals contributed the least.