Density functional analysis of the simultaneous charge/spin order and the associated Cu-Fe intersite charge transfer in LaCu3Fe4O12

TL;DR

This study uses density functional theory to analyze the phase transition in LaCu3Fe4O12, revealing how electronic interactions drive simultaneous charge and spin ordering and associated Cu-Fe charge transfer.

Contribution

It provides a detailed electronic mechanism explaining the coupled charge and spin order transition in LaCu3Fe4O12, highlighting the roles of magnetic exchange and band width effects.

Findings

Charge and spin order occur simultaneously at 393 K.

Electronic effects like magnetic exchange influence the phase transition.

Band width dependence on spin order affects charge transfer.

Abstract

LaCu3Fe4O12 undergoes a phase transition at 393 K involving the spin order (SO) of the Fe sites and the charge order (CO) resulting in Cu-Fe intersite charge transfer. On the basis of density functional calculations, we show that this simultaneous CO/SO phenomenon is a consequence of two electronic effects, namely, the competition between the Fe-Fe and Fe-Cu antiferromagnetic spin exchange and the dependence of the width of the Fe d-block bands on the SO of the Fe atoms.