title: Spectroscopic STM studies of single gold(III) porphyrin molecules.
abstract: Low-temperature scanning tunneling microscopy, a well-established technique for single-molecule investigations in an ultrahigh vacuum environment, has been used to study the electronic properties of Au(III) 5,10,15,20-tetraphenylporphyrin (AuTPP) molecules on Au(111) at the submolecular scale. AuTPP serves as a model system for chemotherapeutically relevant Au(III) porphyrins. For the first time, real-space images and local scanning tunneling spectroscopy data of the frontier molecular orbitals of AuTPP are presented. A comparison with results from density functional theory reveals significant deviations from gas-phase behavior due to a non-negligible molecule/substrate interaction. We identify the oxidation state of the central metal ion in the adsorbed AuTPP as Au(3+).
authors.affiliation: Department of Solid State Physics and Institute of Inorganic Chemistry, Johannes Kepler University, Altenbergerstrasse 69, 4040 Linz, Austria. stefan.muellegger@jku.at
authors.forename: Stefan
authors.initials: S
authors.lastname: Müllegger
authors.forename: Wolfgang
authors.initials: W
authors.lastname: Schöfberger
authors.forename: Mohammad
authors.initials: M
authors.lastname: Rashidi
authors.forename: Lorenz M
authors.initials: LM
authors.lastname: Reith
authors.forename: Reinhold
authors.initials: R
authors.lastname: Koch
mesh_terms: D003198:Computer Simulation; D006046:Gold / Q000737:chemistry*; D016252:Microscopy, Scanning Tunneling / Q000379:methods*; D008956:Models, Chemical; D009942:Organometallic Compounds / Q000737:chemistry*; D010316:Particle Size; D011166:Porphyrins / Q000737:chemistry*; D013499:Surface Properties; D013696:Temperature
chemical_list: C509964:5,10,15,20-tetraphenylporphyrin; D009942:Organometallic Compounds; D011166:Porphyrins; D006046:Gold