Exchange-correlation energy of a three-dimensional electron gas in a magnetic field

We present the results of random-phase-approximation calculations of the ground-state exchange and correlation energy of a uniform electron liquid in strong and intermediate magnetic fields (one or several Landau subbands populated), including arbitrary spin polarization. Applications for the current and spin-density-functional theory are discussed and appropriate effective potentials are constructed. We investigate the exchange and correlation effects on the nondissipative currents, the Landau subband occupation, and on the shape of the exchange-correlation hole. In an appendix we present a numerical fit for the exchange-correlation energy.