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Nanometer-Scale Probing Of Potential-Dependent Electrostatic Forces, Adhesion, And Interfacial Friction At The Electrode/Electrolyte Interface, Shane D. Campbell, Andrew C. Hillier
Nanometer-Scale Probing Of Potential-Dependent Electrostatic Forces, Adhesion, And Interfacial Friction At The Electrode/Electrolyte Interface, Shane D. Campbell, Andrew C. Hillier
Andrew C. Hillier
The atomic force microscope (AFM) was used to examine the influence of an applied electrochemical potential on the interfacial properties of the electrode/electrolyte interface. Measurements of electrostatic force, adhesion, and friction coefficient were performed at two different electrode surfaces: glassy carbon anda thin film of sulfonate-derivatized poly(aniline) (SPANi). At the carbon electrode, changes in electrostatic force between probe and substrate exhibited a potential-dependent transition from repulsive to attractive values at potentials negative and positive of the potential of zero charge (Epzc). Simultaneous measurements of tip-substrate adhesion and friction coefficient showed a change from low to high values over the same …
The Physicochemical Origins Of Coincident Epitaxy In Molecular Overlayers: Lattice Modeling Vs Potential Energy Calculations, Julie A. Last, Daniel E. Hooks, Andrew C. Hillier, Michael D. Ward
The Physicochemical Origins Of Coincident Epitaxy In Molecular Overlayers: Lattice Modeling Vs Potential Energy Calculations, Julie A. Last, Daniel E. Hooks, Andrew C. Hillier, Michael D. Ward
Andrew C. Hillier
The physicochemical basis for epitaxial stabilization of coincident molecular overlayers is illustrated by comparison of optimum overlayer-substrate configurations calculated with potential energy (PE) methods and a simple geometric lattice misfit modeling algorithm (EpiCalc) that neglects molecular orientations and intermolecular potentials. Using â-bis(ethylenedithio)tetrathiafulvalene triiodide (â-ET2I3), perylenetetracarboxylic diimide (PTCDI), and perylenetetracarboxylic dianhydride (PTCDA) overlayers on a graphite substrate as examples, both methods predict identical optimum azimuthal overlayer orientations for each overlayer that also agree with experimental observations. PE calculations for three hypothetical PTCDA overlayers, with identical lattice parameters but different molecular orientations, predict coincidence at the same azimuthal orientation for all overlayers. …