The orbital and charge ordering in Pr_{1-x}Ca_xMnO_3 (x=0 and 0.5) from the ab initio calculations

TL;DR

This study uses ab initio calculations to explore the electronic, charge, and orbital ordering in Pr_{1-x}Ca_xMnO_3, successfully reproducing experimental observations without Jahn-Teller distortions.

Contribution

It demonstrates that LSDA+U calculations can accurately model orbital and charge ordering in doped manganites without lattice distortions, aligning with experimental data.

Findings

Correct ground state for x=0.5 is a charge and orbital ordered antiferromagnetic insulator.

No Jahn-Teller distortions are needed to reproduce orbital ordering in undoped PrMnO_3.

Results agree well with neutron diffraction data.

Abstract

The electronic structure of the doped manganites Pr$_{1-x}$Ca$_x$MnO$_3$ was calculated by the LSDA+U method which takes into account the local Coulomb interaction between d-electrons of transition metal ions. In contrast to the standard local spin density approximation (LSDA) no Jahn-Teller lattice distortions are needed to reproduce the experimentally observed orbital ordering in the undoped PrMnO$_3$. The correct ground state : a charge and orbital ordered antiferromagnetic insulator, was obtained for Pr$_{1/2}$Ca$_{1/2}$MnO$_3$. The results are in good agreement with the neutron diffraction data.