Gradient corrections to the exchange-correlation free energy

@article{Sjostrom2014GradientCT,
  title={Gradient corrections to the exchange-correlation free energy},
  author={Travis Sjostrom and J{\'e}r{\^o}me Daligault},
  journal={Physical Review B},
  year={2014},
  volume={90},
  pages={155109}
}
We develop the first-order gradient correction to the exchange-correlation free energy of the homogeneous electron gas for use in finite-temperature density functional calculations. Based on this, we propose and implement a simple temperature-dependent extension for functionals beyond the local density approximation. These finite-temperature functionals show improvement over zero-temperature functionals, as compared to path-integral Monte Carlo calculations for deuterium equations of state, and… 

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