Structural response to O*-O' and magnetic transitions in orthorhombic perovskites

TL;DR

This study investigates how the crystal structure of orthorhombic perovskites La1-xCaxMnO3 evolves with temperature, revealing structural changes associated with magnetic transitions from insulating to metallic states.

Contribution

It provides a detailed twin model for structure determination of twinned orthorhombic perovskites using single crystal x-ray diffraction data.

Findings

Structural evolution from insulating to metallic states.

Successful modeling of twin relations in the crystal structure.

Full structure determination with multiple twin fractions.

Abstract

We present a temperature dependent single crystal x-ray diffraction study of twinned orthorhombic perovskites La1-xCaxMnO3, for x=0.16 and x=0.25. These data show the evolution of the crystal structure from the ferromagnetic insulating state to the ferromagnetic metallic state. The data are modelled in space group Pnma with twin relations based on a distribution of the b axis over three perpendicular cubic axes. The twin model allows full structure determination in the presence of up to six twin fractions using the single crystal x-ray diffraction data.