Density functional theory plus dynamical mean field theory within the framework of linear combination of numerical atomic orbitals: Formulation and benchmarks

TL;DR

This paper develops a formalism to integrate density functional theory with dynamical mean-field theory within the linear combination of numerical atomic orbitals framework, enabling more accessible and versatile first-principles calculations for strongly correlated materials.

Contribution

It introduces a new formalism and implementation for combining NAO-based DFT codes with DMFT impurity solvers, validated through extensive benchmarks.

Findings

Successfully merged NAO-based DFT with DMFT solvers

Validated approach on transition metals, lanthanides, and actinides

Facilitates advanced beyond-DFT methods with DMFT integration

Abstract

The combination of density functional theory with dynamical mean-field theory (DFT+DMFT) has become a powerful first-principles approach to tackle strongly correlated materials in condensed matter physics. The wide use of this approach relies on robust and easy-to-use implementations, and its implementation in various numerical frameworks will increase its applicability on the one hand and help crosscheck the validity of the obtained results on the other. In the work, we develop a formalism within the linear combination of numerical atomic orbital (NAO) basis set framework, which allows for merging NAO-based DFT codes with DMFT quantum impurity solvers. The formalism is implemented by interfacing two NAO-based DFT codes with three DMFT impurity solvers, and its validity is testified by benchmark calculations for a wide range of strongly correlated materials, including 3\textit{d} transition metal compounds, lanthanides, and actinides. Our work not only enables DFT+DMFT calculations using popular and rapidly developing NAO-based DFT code packages, but also facilitates the combination of more advanced beyond-DFT methodologies available in this codes with the DMFT machinery.