9522286 Halley This project constructs computational models to describe the electrode-electrolyte interface, with particular emphasis on models of metal electrodes and aqueous electrolytes. Using direct dynamics methods, which have not been applied to these interfaces by others before, the electronic structure of the constituents of the interface is recalculated at each step of the simulation of the atomic motion. More traditional methods are qualitatively incorrect because of the mobility of the molecules of the liquid. Preliminary work is being improved upon in several stages, beginning with the inclusion of nonlocal pseudopotentials and various computational improvements to study the potential dependence of the interfacial capacitance. The next stage studies the reconstruction of noble metal surfaces under potential control in electrochemical environments. The third stage investigates deposition and dissolution. Progress in the proposed directions will contribute to understanding chemical reactions at interfaces in diverse technological contexts, including catalysis, corrosion, electroplating, and the understanding, development, and improvement of microelectronic processing techniques and advanced batteries. %%% This project constructs computer models to describe the electrode-electrolyte interface, with particular emphasis on models of metal electrodes and aqueous electrolytes. Such interfaces are found in batteries, fuel cells, corrosive environments, and in the electronics industry. The investigators have developed preliminary computer codes of a type that no other has ever applied to such systems. Other, more conventional approaches fail because they do not do a good job describing the liquid. The project proceeds in three states of increasing complexity, eventually addressing the change in the structure of the metal surface, and adding material to or taking material away from the metal surface. Progress in the proposed directions will contr ibute to understanding chemical reactions at interfaces in diverse technological contexts, including catalysis, corrosion, electroplating, and the understanding, development, and improvement of microelectronic processing techniques and advanced batteries. ***
