Exchange-correlation potentials for spin-polarized systems at finite temperatures

The exchange and correlation contributions to the thermodynamic free energy and the corresponding exchange-correlation potential ($V_{\mathrm{xc}\mathrm{\sigma }}$) are evaluated for a spin-polarized electron gas over a wide range of temperatures and densities. The exchange-correlation potential is parameterized for easy usage in local-spin-density calculations. The result indicates that for t≤0.15 (t=T/$T_F$), the temperature dependence of $V_{\mathrm{xc}\mathrm{\sigma }}$ is negligibly small. The effects of the spin polarization are most significant for t<3. Our results for $V_{\mathrm{xc}}$ for an unpolarized system agree well with those of a previous calculation by Perrot and Dharma-wardana.