Quantum Monte Carlo study of the relativistic spin-polarized jellium

We apply the variational and fixed-node diffusion quantum Monte Carlo methods to calculate the ground state energy of the unpolarized (xi = 0) and fully polarized (xi = 1) homogeneous electron gas at zero temperature within the density range r(s) = 0.1-10.0, incorporating relativistic effects via first-order perturbation theory. The relativistic correction terms are compared with the Hartree-Fock expectation values. It is found that electron correlation is significant at intermediate densities r(s) similar to 1.0-5.0. This demonstrates the importance of a proper treatment of electron correlation in RDFT calculations.