Ab initio description of bcc iron with correlation matrix renormalization theory

TL;DR

This paper applies the ab initio Correlation Matrix Renormalization Theory to ferromagnetic bcc iron, successfully reproducing physical properties and analyzing local electronic correlations to distinguish roles of different electronic states.

Contribution

It demonstrates the effectiveness of CMRT in modeling ferromagnetic bcc iron and provides detailed insights into the local electronic correlations of $t_{2g}$ and $e_g$ states.

Findings

Reproduced equilibrium physical properties of bcc iron.

Analyzed local electronic correlations of $t_{2g}$ and $e_g$ states.

Highlighted the different roles of electronic states in spin channels.

Abstract

We applied the ab initio spin-polarized Correlation Matrix Renormalization Theory (CMRT) to the ferromagnetic state of the bulk BCC iron. We showed that it was capable of reproducing the equilibrium physical properties and the pressure-volume curve in good comparison with experiments. We then focused on the analysis of its local electronic correlations. By exploiting different local fluctuation-related physical quantities as measures of electronic correlation within target orbits, we elucidated the different roles of $t_{2g}$ and $e_g$ states in both spin channels and presented compelling evidence to showcase this distinction in their electronic correlation.