摘要
In quantum chemical calculations with the LCAO-MO method, atomic orbitals are generally represented by Slater-type orbitals (STO). But in nonempirical calculations such as ab initio, a serious difficulty was encountered when STO was used in evaluation of multi-center integrals. In 1950, Boys suggested to expand STO in terms of a combination of Gaussiantype orbitals (GTO) and then evaluate molecular integrals with the latter. Since that
