徐光宪同系能级公式的重新推导

Derivation of the Xu's Homologous Energy Level Formula

用差分方程法完整地推导出徐光宪等人提出的同系能级公式：Ｅ（ｎ，ｋ）＝ａ＋ｂ２ｋ－１ｋｓｉｎｋπ２Ｎ＋１，其中ｋ为能级序数，ｋ＝１，２，…，ｎ，Ｎ＝ｎ＋ｔ，ｎ为同系序数，ｔ为端基指数，Ｎ为有效同系序数．该法比以往用分子轨道图形理论进行推导的过程更为简单直观．

A new way using the difference equation method to obtain the Xu's homologous energy level formula is presented,which is simpler and easier than using the theory of molecular orbitalgraph.