CALTECH ASCI TECHNICAL REPORT 115 cit-asci-tr115 Accurate Calculations of the Peierls Stress in Small Periodic Cells
نویسندگان
چکیده
The Peierls stress for a [111]-screw dislocation in bcc Tantalum is calculated using an embedded atom potential. More importantly, a method is presented which allows accurate calculations of the Peierls stress in the smallest periodic cells. This method can be easily applied to ab initio calculations, where only the smallest unit cells capable of containing a dislocation can be conviently used. The calculation speci cally focuses on the case where the maximum resolved shear stress is along a f110g-plane.
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