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Oxidation of aluminum nanoclusters is investigated with a parallel molecular-dynamics approach based on dynamic charge transfer among atoms. Structural and dynamic correlations reveal that significant charge transfer gives rise to large negative pressure in the oxide which dominates the positive pressure due to steric forces. As a result, aluminum moves outward and oxygen moves towards the interior of the cluster with the aluminum diffusivity 60% higher than that of oxygen. A stable 40 Å thick amorphous oxide is formed; this is in excellent agreement with experiments. [S0031-9007(99)09416-8]

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The reduction of trichloroethylene (TCE) and tetrachloroethylene (PCE) was examined in ananaerobic batch vapor–water system containing metallic iron. Concentrations of the parent compounds and products (some of which went on to react further) were determined at discrete time intervals during the reactions by analysis of the headspace vapor. cis‐1,2‐Dichloroethylene, 1,1‐dichloroethylene, vinyl chloride, methane, chloroacetylene, acetylene, ethylene, ethane, and C3–5 alkenes and alkanes were observed as products from both compounds. Trichloroethylene was also observed from the reduction of PCE. The masses of unreacted polychlorinated ethylenes sorbed on the iron surface were significant based upon previously determined sorption isotherms, and were incorporated in carbon and chloride recovery estimates. Final carbon and chlorine recoveries of 76% and 104%, respectively, were obtained after a 92% loss of the initial TCE. After the loss of 74% of the initial PCE, the final carbon and chlorine recoveries were 90% and 118%, respectively. Reaction pathways, which include both hydrogenolysis and reductive β‐elimination, are proposed to account for the observed products.

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