title: Mapping Atomic Orbitals with the Transmission Electron Microscope: Images of Defective Graphene Predicted from First-Principles Theory.
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.
authors.affiliation: Physics Department and IRIS Adlershof, Humboldt-Universität zu Berlin, 12489 Berlin, Germany.
authors.forename: Lorenzo
authors.initials: L
authors.lastname: Pardini
authors.affiliation: Institute of Solid State Physics, Vienna University of Technology, A-1040 Vienna, Austria.|University Service Centre for Transmission Electron Microscopy, Vienna University of Technology, A-1040 Vienna, Austria.|Department of Materials Science and Engineering, McMaster University, Hamilton, Ontario L8S 4L8, Canada.
authors.forename: Stefan
authors.initials: S
authors.lastname: Löffler
authors.affiliation: Physics Department and IRIS Adlershof, Humboldt-Universität zu Berlin, 12489 Berlin, Germany.
authors.forename: Giulio
authors.initials: G
authors.lastname: Biddau
authors.affiliation: Electron Microscopy Group of Materials Science, University of Ulm, 89081 Ulm, Germany.|Fraunhofer Institute for Applied Optics and precision engineering IOF, 07749 Jena, Germany.
authors.forename: Ralf
authors.initials: R
authors.lastname: Hambach
authors.affiliation: Electron Microscopy Group of Materials Science, University of Ulm, 89081 Ulm, Germany.
authors.forename: Ute
authors.initials: U
authors.lastname: Kaiser
authors.affiliation: Physics Department and IRIS Adlershof, Humboldt-Universität zu Berlin, 12489 Berlin, Germany.|European Theoretical Spectroscopy Facility (ETSF).
authors.forename: Claudia
authors.initials: C
authors.lastname: Draxl
authors.affiliation: Institute of Solid State Physics, Vienna University of Technology, A-1040 Vienna, Austria.|University Service Centre for Transmission Electron Microscopy, Vienna University of Technology, A-1040 Vienna, Austria.
authors.forename: Peter
authors.initials: P
authors.lastname: Schattschneider