一、引言 锕系元素处于周期表最后一个周期——第七周期。对于第七周期的原子来说,由于其电子结构的复杂性,导致价态变化的复杂性,同种元素在不同化合物中的价电子结构是完全不同的。因此,研究锕系元素及其化合物的电子结构是具有重要的理论意义的。锕系元素是原子能工业的重要原料,对锕系元素,特别是对其价电子结构的研究,有利于促进对锕系元素的开发 I. Introduction Actinides in the last cycle of the periodic table - the seventh cycle. For the seventh cycle of atoms, due to the complexity of their electronic structure, resulting in the complexity of valence changes, the valence electron structure of the same species in different compounds is completely different. Therefore, the study of the electronic structure of actinides and their compounds is of great theoretical significance. Actinides are important raw materials for atomic energy industry. The study of actinides, especially their valence and electron structures, is helpful to the development of actinides