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تسجيل مستخدم جديدIsland Shape Controls Magic-Size Effect for Heteroepitaxial Diffusion
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Lattice mismatch of Cu on Ag(111) produces fast diffusion for special magic sizes of islands. A size- and shape-dependent reptation mechanism is responsible for low diffusion barriers. Initiating the reptation mechanism requires a suitable island shape, a property not considered in previous studies of 1D island chains and 2D closed-shell islands. Shape determines the dominant diffusion mechanism and leads to multiple clearly identifiable magic-size trends for diffusion depending on the number of atoms whose bonds are shortened during diffusion.
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Henry H. Wu
, Dallas R. Trinkle (Department of Materials Science andn Engineering
, University of Illinois
2009
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