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

摘要

Transmission electron microscopy has been a promising candidate for mappingatomic orbitals for a long time. Here, we explore its capabilities by a firstprinciples approach. For the example of defected graphene, exhibiting either anisolated vacancy or a substitutional nitrogen atom, we show that threedifferent kinds of images are to be expected, depending on the orbitalcharacter. To judge the feasibility of visualizing orbitals in a realmicroscope, the effect of the optics aberrations is simulated. We demonstratethat, by making use of energy-filtering, it should indeed be possible to mapatomic orbitals in a state-of-the-art transmission electron microscope.