对称性匹配原则是LCAO-MO的基本原则。一般从AO或MO的中心对称性出发,或仅根据一两个对称操作做出判断,显然是不妥的。也有的用含键轴的全部对称操作逐个地进行考察,无疑是正确的,但过于繁琐。本文从两AO的重叠积分和LCAO的一般原则出发,提供一个简明而严格的判据,并进一步从理论和算法上讨论、计算了匹配的可能重叠数。关 Symmetry matching principle is the basic principle of LCAO-MO. In general, starting from the central symmetry of AO or MO, or judging based on only one or two symmetrical operations, it is obviously not proper. There are some with the key axis of all the symmetry of the operation to examine one by one, is undoubtedly correct, but too cumbersome. Based on the principle of overlap of two AO and the general principle of LCAO, this paper provides a concise and rigorous criterion, and further discusses the theory and algorithm, and calculates the possible overlap number of the match. turn off