Strong Magneto-elastic coupling in VOCl: Neutron and synchrotron powder x-ray diffraction study

TL;DR

This study reveals strong magnetoelastic coupling in VOCl, where magnetic ordering induces structural distortion, demonstrated through combined neutron and synchrotron diffraction techniques.

Contribution

It provides detailed insights into the magnetoelastic effects in VOCl, highlighting the coupling between magnetic order and structural changes.

Findings

Antiferromagnetic order causes monoclinic distortion.

Magnetoelastic coupling affects structural parameters.

Structural anomalies occur in the paramagnetic phase.

Abstract

We present a combined neutron and synchrotron powder diffraction study of the crystal and magnetic structure of VOCl. The occurrence of antiferromagnetic order in VOCl is accompanied by a monoclinic distortion. The high sensitivity of the magnetic interaction parameters on V-O-V bond angles and V-V distances yields strong magnetoelastic coupling which implies the structural distortion below T$_N$ as well as anomalous structural effects in the paramagnetic phase.