Molecular structure elucidation with charge-state control

Abstract

The charge state of a molecule governs its physicochemical properties, such as conformation, reactivity and aromaticity, with implications for on-surface synthesis, catalysis, photo conversion and applications in molecular electronics. On insulating, multilayer NaCl films we control the charge state of organic molecules and resolve their structures in neutral, cationic, anionic and dianionic states by atomic force microscopy, obtaining atomic resolution and bond-order discrimination using CO functionalized tips. We detect changes in conformation, adsorption geometry and bond-order relations for azobenzene, tetracyanoquinodimethane and pentacene in multiple charge states. Moreover, for porphine we investigate the charge-state-dependent change of aromaticity and conjugation pathway in the macrocycle. This work opens the way to studying chemical-structural changes of individual molecules for a wide range of charge states.

References in corpus (4)

• The mechanism of high-resolution STM/AFM imaging with functionalized tips
• The origin of high-resolution IETS-STM images of organic molecules with functionalized tips
• Tuning the conductance of a molecular switch
• Detection of Single Electron Charging in an Individual InAs Quantum Dot by Noncontact Atomic Force Microscopy