The dependence of exchange and coulomb energies on wave functions of the interacting systems

摘要: First-order energies have been calculated for the He2 system using a number of He wave functions. The convergence to Hartree-Fock limit has studied and two-term expansion in Slater orbitals gives about 98 per cent this limit. effect correlation examined by adding s′2 p 2 configurations function change approximately 10 effective first-order energy noted.