Real-space mapping of electronic orbitals

TL;DR

This paper demonstrates real-space mapping of electronic orbitals in bulk TiO2 using electron energy-loss spectrometry, enabling direct visualization of atomic bonds and electronic states at the nanoscale.

Contribution

It introduces a novel experimental approach to visualize electronic states at the atomic scale, bridging the gap between theory and observation.

Findings

Mapped p and d electronic transitions at Ångström scale

Verified theoretical predictions of electronic states experimentally

Enabled investigation of electronic states at defects and interfaces

Abstract

Electronic states are responsible for most material properties, including chemical bonds, electrical and thermal conductivity, as well as optical and magnetic properties. Experimentally, however, they remain mostly elusive. Here, we report the real-space mapping of selected transitions between p and d states on the {\AA}ngstr\"om scale in bulk rutile (TiO2) using electron energy-loss spectrometry (EELS), revealing information on individual bonds between atoms. On the one hand, this enables the experimental verification of theoretical predictions about electronic states. On the other hand, it paves the way for directly investigating electronic states under conditions that are at the limit of the current capabilities of numerical simulations such as, e.g., the electronic states at defects, interfaces, and quantum dots.