Direct observation of charge mediated lattice distortions in complex oxide solid solutions

TL;DR

This study employs advanced electron microscopy to directly observe atomic-scale displacements caused by local chemistry in complex oxide solid solutions, revealing how charge-mediated distortions influence material properties.

Contribution

It provides the first direct real-space measurements of picometer-scale atomic displacements in complex oxides, correlating experimental observations with theoretical predictions and charge distribution analysis.

Findings

Atomic displacements are correlated with local chemistry.

Displacements match density functional theory predictions.

Charge distribution influences lattice distortions.

Abstract

Material properties depend sensitively on picometer scale atomic displacements introduced by local chemical fluctuations. Direct real-space, high spatial-resolution measurements of this compositional variation and corresponding distortion can provide new insights into materials behavior at the atomic scale. Using aberration corrected scanning transmission electron microscopy combined with advanced imaging methods, we observed atom column specific, picometer-scale displacements induced by local chemistry in a complex oxide solid solution. Displacements predicted from density functional theory were found to correlate with the observed experimental trends. Further analysis of bonding and charge distribution were used to clarify the mechanisms responsible for the detected structural behavior. By extending the experimental electron microscopy measurements to previously inaccessible length scales, we identified correlated atomic displacements linked to bond differences within the complex oxide structure.