Molecular integrals in the generalized hylleraas–CI method

In the generalized Hylleraas-CI method, the original correlation factor r ij ν is multiplied by a Gaussian geminal. Using the approach of generating functions, the general formulas of molecular integrals in this method are derived over Cartesian Gaussian orbitals. From differentiations of the generating functions, the expanding length in the incomplete Gamma functions is reduced, and some cancellations presented in other approaches are avoided. Preliminary calculations for H 2 and H 2 -H 2 systems are carried out over STO-3G basis. The results are encouraging

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