Towards a Coherent Treatment of the Self-Consistency and the Environment-Dependency in a Semi-Empirical Hamiltonian for Materials Simulation
The construction of semi-empirical Hamiltonians for materials that have the predictive power is an urgent task in materials simulation. This task is necessitated by the bottleneck encountered in using density functional theory (DFT)-based molecular dynamics (MD) schemes for the determination of structural properties of materials. Although DFT/MD schemes are expected to have predictive power, they can only be applied to systems of about a few hundreds of atoms at the moment. MD schemes based on tight-binding (TB) Hamiltonians, on the other hand, are much faster and applicable to larger systems. However, the conventional TB Hamiltonians include only two-center interactions and they do not have the framework to allow the self-consistent determination of the charge redistribution. Therefore, in the strictest sense, they can only be used to provide explanation for system-specific experimental results. Specifically, their transferability is limited and they do not have predictive power. To overcome the size limitation of DFT/MD schemes on the one hand and the lack of transferability of the conventional two-center TB Hamiltonians on the other, there exists an urgent need for the development of semi-empirical Hamiltonians for materials that are transferable and hence, have predictive power.
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- D.A. Papaconstantopoulos, M.J. Mehl, S.C. Erwin et al., “Tight-binding Hamiltonians for carbon and silicon”, In: P.E.A. Turchi, A. Gonis and L. Colombo (eds.), Tight Binding Approach to Computational Materials Science. MRS Symposia Proceedings No. 491, Materials Research Society, Pittsburg, pp. 221–230, 1998.Google Scholar
- C. Leahy, M. Yu, C.S. Jayanthi, and S.Y Wu, “Self-consistent and environment dependent Hamiltonians for materials simulations: case studies on Si structures”, http://xxx.lanl.gov/list/cond-mat/0402544, 2004.