Bond-order potential for simulations of extended defects in tungsten

作者:Mrovec M*; Groeger R; Bailey A G; Nguyen Manh D; Elsaesser C; Vitek V
来源:Physical Review B, 2007, 75(10): 104119.
DOI:10.1103/PhysRevB.75.104119

摘要

We present a bond-order potential (BOP) for the bcc transition metal tungsten. The bond-order potentials are a real-space semiempirical scheme for the description of interatomic interactions based on the tight-binding approximation. In the hierarchy of atomic-scale-modeling methods the BOPs thus provide a direct bridge between electronic-structure and atomistic techniques. Two variants of the BOP were constructed and extensively tested against accurate first-principles methods in order to assess the potentials' reliability and applicability. A comparison of the BOP with a central-force potential is used to demonstrate that a correct description of directional mixed covalent and metallic bonds is crucial for a successful and fully transferable model. The potentials are applied in studies of low-index surfaces, symmetrical tilt grain boundaries, and dislocations.

  • 出版日期2007-3