Efficient and accurate treatment of electron correlations from first-principles

TL;DR

This paper introduces an efficient abab initiobb method for accurately calculating electronic structures of strongly correlated systems, overcoming limitations of existing approaches with no adjustable parameters and good performance on challenging problems.

Contribution

The authors extend the Gutzwiller approximation to evaluate two-particle operators, providing a parameter-free, accurate, and computationally efficient method for strongly correlated electron systems.

Findings

Accurately describes bonding and dissociation in hydrogen and nitrogen clusters.

Comparable to high-level quantum chemistry calculations in accuracy.

Handles challenging problems in density functional theory.

Abstract

We present an efficient \textit{ab initio} method for calculating the electronic structure and total energy of strongly correlated electron systems. The method extends the traditional Gutzwiller approximation for one-particle operators to the evaluation of the expectation values of two particle operators in a full many-electron Hamiltonian. The method is free of adjustable Coulomb parameters, and has no double counting issues in the calculation of total energy, and has the correct atomic limit. We demonstrate that the method describes well the bonding and dissociation behaviors of the hydrogen and nitrogen clusters. We also show that the method can satisfactorily tackle great challenging problems faced by the density functional theory recently discussed in the literature. The computational workload of our method is similar to the Hartree-Fock approach while the results are comparable to high-level quantum chemistry calculations.