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Exchange-correlation entropy from the generalized thermal adiabatic connection
Brittany P Harding1, Zachary Mauri2, Vera W Xie1
1University of California, Merced, 5200 North Lake Road, Merced, California 95343, USA.
The Journal of Chemical Physics
|April 17, 2024
Summary
A new generalized thermal adiabatic connection (GTAC) formula was developed to calculate exchange-correlation entropy in warm dense matter. This method enables better simulations of this energetic quantum phase.
Area of Science:
- Condensed Matter Physics
- Quantum Mechanics
- Computational Physics
Background:
- Warm dense matter (WDM) is an energetic state with strong correlations and quantum effects.
- Simulating WDM relies on thermal density functional theory (TDFT).
- Accurate TDFT requires temperature-dependent exchange-correlation approximations.
Purpose of the Study:
- To introduce a generalized thermal adiabatic connection (GTAC) formula for WDM.
- To enable extraction of exchange-correlation entropy (SXC) using simulated interaction strength scaling.
- To provide a new framework for studying WDM properties.
Main Methods:
- Development of the generalized thermal adiabatic connection (GTAC) formula with a fictitious temperature parameter.
- Application of simulated interaction strength scaling.
- Utilizing a Hellmann-Feynman approach to derive SXC from the exchange-correlation potential.
Main Results:
- The GTAC formula successfully extracts exchange-correlation entropy (SXC).
- SXC analysis as a function of interaction strength suggests new approximation forms.
- The GTAC framework facilitates exploration of temperature, density, and interaction strength interplay.
Conclusions:
- The proposed GTAC formula offers a novel method for calculating SXC in WDM.
- GTAC provides a versatile framework for developing improved TDFT approximations.
- This work advances the understanding and simulation of warm dense matter.
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