Mapping atomic orbitals with the transmission electron microscope: Images of defective graphene predicted from first-principles theory

TL;DR

This paper demonstrates, through first-principles simulations, that modern transmission electron microscopes can visualize atomic orbitals in defective graphene, considering effects like optical aberrations and energy-filtering.

Contribution

It provides a theoretical framework and simulation results showing the feasibility of mapping atomic orbitals in defective graphene using advanced electron microscopy techniques.

Findings

Atomic orbitals can be distinguished based on image types.

Optical aberrations affect the clarity of orbital images.

Energy-filtering enhances the visualization of atomic orbitals.

Abstract

Transmission electron microscopy has been a promising candidate for mapping atomic orbitals for a long time. Here, we explore its capabilities by a first principles approach. For the example of defected graphene, exhibiting either an isolated vacancy or a substitutional nitrogen atom, we show that three different kinds of images are to be expected, depending on the orbital character. To judge the feasibility of visualizing orbitals in a real microscope, the effect of the optics aberrations is simulated. We demonstrate that, by making use of energy-filtering, it should indeed be possible to map atomic orbitals in a state-of-the-art transmission electron microscope.