# 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…

## 35 Citations

### Thermal Corrections to Density Functional Simulations of Warm Dense Matter

- Physics
- 2015

Present density functional calculations of warm dense matter often use the Mermin-Kohn-Sham (MKS) scheme at finite temperature, but employ ground-state approximations to the exchange-correlation (XC)…

### Exact thermal density functional theory for a model system: Correlation components and accuracy of the zero-temperature exchange-correlation approximation

- Physics
- 2016

Thermal density functional theory calculations often use the Mermin-Kohn-Sham scheme, but employ ground-state approximations to the exchange-correlation (XC) free energy. In the simplest solvable…

### Nonempirical Semilocal Free-Energy Density Functional for Matter under Extreme Conditions.

- PhysicsPhysical review letters
- 2018

Systematic construction of a generalized gradient approximation XC free- energy functional based on rigorous constraints, including the free-energy gradient expansion, which provides the correct temperature dependence in the slowly varying regime and the correct zero-T, high- T, and homogeneous electron gas limits.

### Two-temperature warm dense hydrogen as a test of quantum protons driven by orbital-free density functional theory electronic forces

- Physics
- 2020

We consider a steady-state (but transient) situation in which a warm dense aggregate is a two-temperature system with equilibrium electrons at temperature Te, ions at Ti, and Te ≠ Ti. Such states are…

### Influence of finite temperature exchange-correlation effects in hydrogen

- Physics
- 2020

We use density functional molecular dynamics (DFT-MD) to study the effect of finite temperature exchange-correlation (xc) in Hydrogen. Using the Kohn-Sham approach, the xc energy of the system,…

### Momentum distribution of the uniform electron gas at finite temperature: Effects of spin polarization.

- PhysicsPhysical review. E
- 2021

It is found that interesting physical effects like the interaction-induced increase in the occupation of the zero-momentum state n(0) substantially depend on ξ, and the current understanding of the UEG as a fundamental model system is advanced.

### Ab initio Exchange-Correlation Free Energy of the Uniform Electron Gas at Warm Dense Matter Conditions.

- PhysicsPhysical review letters
- 2017

By closing the gap to the ground state and by performing extensive QMC simulations for different spin polarizations, the first completely ab initio exchange-correlation free energy functional is obtained; the accuracy achieved is an unprecedented ∼0.3%.

### Ab Initio Quantum Monte Carlo Simulation of the Warm Dense Electron Gas in the Thermodynamic Limit.

- Physics, ChemistryPhysical review letters
- 2016

Extensive new QMC results for up to N=1000 electrons enable us to compute the potential energy V and the exchange-correlation free energy F_{xc} of the macroscopic electron gas with an unprecedented accuracy.

### Theoretical foundations of quantum hydrodynamics for plasmas

- Physics
- 2017

Beginning from the semiclassical Hamiltonian, the Fermi pressure and Bohm potential for the quantum hydrodynamics application (QHD) at finite temperature are consistently derived in the framework of…

### Thermal stitching: Extending the reach of quantum fermion solvers

- Physics
- 2018

For quantum fermion problems, many accurate solvers are limited by the temperature regime in which they can be usefully applied. The Mermin theorem implies the uniqueness of an effective potential…