Ab initiocalculation of atomic solid hydrogen phases based on Gutzwiller many-body wave functions

Area of Science:

• Condensed Matter Physics
• Computational Quantum Chemistry

Background:

• Accurate theoretical modeling of crystalline hydrogen phases is crucial for understanding materials under extreme conditions.
• Existing methods like Density-Functional Theory (DFT) often struggle with strong electron correlation effects.
• Ab initio many-body methods offer a path to higher accuracy but can be computationally demanding.

Purpose of the Study:

• To investigate crystalline phases of atomic hydrogen using two novel Gutzwiller-based ab initio methods.
• To compare the accuracy and computational efficiency of Correlation Matrix Renormalization Theory (CMRT) and Gutzwiller Conjugate Gradient Minimization (GCGM).
• To benchmark these methods against Quantum Monte Carlo (QMC) and DFT results.

Main Methods:

• Application of Correlation Matrix Renormalization Theory (CMRT) utilizing Gutzwiller wave functions.
• Application of Gutzwiller Conjugate Gradient Minimization (GCGM) based on Gutzwiller wave functions.
• Benchmarking against Quantum Monte Carlo (QMC) and Density-Functional Theory (DFT) results.

Main Results:

• Both CMRT and GCGM provide more accurate results than DFT for crystalline hydrogen.
• GCGM systematically captures more correlation energy than CMRT, leading to improved total energy predictions.
• Incorporating LDA correlation energy (CMRT+Ec) enhances CMRT's agreement with QMC results.

Conclusions:

• CMRT and GCGM are robust ab initio methods for studying correlated electron systems like crystalline hydrogen.
• GCGM offers a significant improvement in accuracy over CMRT for total energy calculations.
• These Gutzwiller-based methods present a viable alternative to empirical parameterizations and computationally expensive techniques.