A new spin-polarized Colle-Salvetti-type correlation energy functional

A new spin-polarized Colle-Salvetti-type dynamical correlation functional is proposed that treats the opposite-spin and parallel-spin correlations. The functional gives good results for total correlation energies and the spin-polarized components for the ground states of the atoms He through Ar. The correlation energies of the excited states and the ground state are well balanced in this treatment, leading to an accurate estimate of the energy difference between two states when the Hartree-Fock methods gives a good description.