Projection-based Density Matrix Renormalization Group in Density Functional Theory Embedding

TL;DR

This paper introduces a novel projection-based embedding method combining DMRG with DFT to accurately describe strongly correlated molecules while improving computational efficiency.

Contribution

It presents the first implementation of DMRG-in-DFT embedding, enabling efficient treatment of large active spaces with strong correlation effects.

Findings

Accurate description of strongly correlated molecular fragments.

Demonstrated effectiveness on proof-of-concept molecules.

Potential for scalable treatment of large systems.

Abstract

The density matrix renormalization group (DMRG) method has already proved itself as a very efficient and accurate computational method, which can treat large active spaces and capture the major part of strong correlation. Its application on larger molecules is, however, limited by its own computational scaling as well as demands of methods for treatment of the missing dynamical electron correlation. In this work, we present the first step in the direction of combining DMRG with density functional theory (DFT), one of the most employed quantum chemical methods with favourable scaling, by means of the projection-based wave function (WF)-in-DFT embedding. On the two proof-of-concept but important molecular examples, we demonstrate that the developed DMRG-in-DFT approach provides a very accurate description of molecules with a strongly correlated fragment.