# Atomic-Scale Structure Relaxation, Chemistry and Charge Distribution of Dislocation Cores in SrTiO3

## TL;DR

This study uses advanced microscopy to reveal atomic structures, chemistry, and charge distribution of dislocation cores in SrTiO3, uncovering two distinct oxygen-deficient core types with different atomic arrangements and chemical properties.

## Contribution

It provides the first atomic-scale characterization of dislocation cores in SrTiO3, identifying their structures, chemistry, and electronic properties with high precision.

## Key findings

- Two types of oxygen deficient dislocation cores identified
- Different atomic arrangements and chemical properties observed
- Presence of vacancies and reconstruction in dislocation cores

## Abstract

By using the state-of-the-art microscopy and spectroscopy in aberration-corrected scanning transmission electron microscopes, we determine the atomic arrangements, occupancy, elemental distribution, and the electronic structures of dislocation cores in the 10{\deg}tilted SrTiO3 bicrystal. We identify that there are two different types of oxygen deficient dislocation cores, i.e., the SrO plane terminated Sr0.82Ti0.85O3-x (Ti3.67+, 0.48<x<0.91) and TiO2 plane terminated Sr0.63Ti0.90O3-y (Ti3.60+, 0.57<y<1). They have the same Burgers vector of a[100] but different atomic arrangements and chemical properties. Besides the oxygen vacancies, Sr vacancies and rocksalt-like titanium oxide reconstruction are also identified in the dislocation core with TiO2 plane termination. Our atomic-scale study reveals the true atomic structures and chemistry of individual dislocation cores, providing useful insights into understanding the properties of dislocations and grain boundaries.

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Source: https://tomesphere.com/paper/1705.03270