Exact double-counting in combining the Dynamical Mean Field Theory and the Density Functional Theory

TL;DR

This paper introduces an exact continuum-based double-counting correction for combining Dynamical Mean Field Theory with Density Functional Theory, improving agreement with experimental data in correlated solids.

Contribution

It derives an exact overlap between DMFT and DFT, providing a more accurate double-counting correction method for correlated materials.

Findings

Improved theoretical-experimental agreement in transition metal oxides.

Better performance of the exact double-counting over traditional methods.

Nominal double-counting aligns closely with the exact approach.

Abstract

We propose a continuum representation of the Dynamical Mean Field Theory, in which we were able to derive an exact overlap between the Dynamical Mean Field Theory and band structure methods, such as the Density Functional Theory. The implementation of this exact double-counting shows improved agreement between theory and experiment in several correlated solids, such as the transition metal oxides and lanthanides. Previously introduced nominal double-counting is in much better agreement with the exact double-counting than most widely used fully localized limit formula.