Using the spin-resolved electronic direct correlation function to estimate the correlation energy of the spin-polarized uniform electron gas

We report a simple ansatz that includes spin-polarization in two different models for the exchange-correlation hole. Both models were originally conceived for the non-polarized uniform electron gas. One of them is based on the electronic direct correlation function, a novel approach to build the long-range behavior of the exchange-correlation hole. This ansatz is shown to work quite well considering the limitations of the original models. …