摘要：

Explicit formulas and numerical tables for the overlap integralSbetween AO's (atomic orbitals) of two overlapping atomsaandbare given. These cover all the most important combinations of AO pairs involvingns, npσ, andnpπ AO's. They are based on approximate AO's of the Slater type, each containing two parameters μ [equal toZ/(n—δ)], andn—δ, wheren—δ is an effective principal quantum number. TheSformulas are given as functions of two parameterspandt,wherep=½(μa+μb)R/aH,Rbeing the interatomic distance, andt=(μa—μb)/(μa+μb). Master tables of computed values ofSare given over wide ranges ofpandtvalues corresponding to actual molecules, and also including the casep=0 (intra‐atomic overlap integrals). In addition, tables of computedSvalues are given for several cases involving 2‐quantums, phybrid AO's. HybridSvalues for any desired type of hybrid can be obtained very easily from the tables as simple linear combinations of non‐hybridSvalues. It is shown howSvalues corresponding to orthogonalized Slater AO's and approximateSvalues for SCF (self‐consistent‐field) AO's can also be obtained as linear combinations of the Slater‐AOSvalues.Svalues for carbon‐carbon 2pσ‐ and 2pπ‐bonds using SCF carbon AO's have been computed (see Table in Section Vb); they correspond to stronger overlap than for Slater AO's. Non‐localized MO group‐orbitalSvalues are also discussed, and are illustrated by an application to H2O. The use of the tables to obtain dipole moments for electronic transitions in certain cases is also mentioned. The use of the tables to obtainSvalues for various specific atom‐pairs and bond‐types, and resulting conclusions, will be discussed in another paper.

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