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

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.