Gaussian-Based Periodic Grand Canonical Density Functional Theory with Implicit Solvation for Computational...

Area of Science:

• Computational Chemistry
• Materials Science
• Electrochemistry

Background:

• Density Functional Theory (DFT) is crucial for materials modeling.
• Simulating solid-state systems under electrochemical conditions presents challenges.
• Existing methods often lack robustness for grand canonical simulations.

Purpose of the Study:

• To introduce a novel numerical method for grand canonical DFT.
• To enhance the simulation of solid-state systems in electrochemical environments.
• To improve the robustness and efficiency of grand canonical simulations.

Main Methods:

• Utilizing Gaussian-type orbitals as the basis set.
• Directly minimizing grand canonical free energy with the density matrix.
• Self-consistently updating electron number during iterations.
• Integrating implicit solvation models for electrochemical applications.

Main Results:

• The new method shows improved robustness compared to plane wave-based approaches.
• Solvation models add less than 50% overhead to gas-phase calculations.
• Accurate modeling of silver surface corrosion was achieved, matching prior studies.

Conclusions:

• The developed method offers a robust and efficient approach for grand canonical DFT in solid-state and electrochemical systems.
• This work paves the way for advanced wave function-based simulations beyond DFT.
• The implementation in Q-Chem facilitates its application in computational chemistry.