Abstract
Ab initio molecular-dynamics (MD) simulations are increasingly being used to study defects in silicon. Simulated quenching and/or conjugate gradient calculations are now common tools to explore the minima of complicated potential energy surfaces. However, the real dynamics are in the constant-temperature runs. These highly computer-intensive simulations are still limited to real times of the order of picoseconds. However, they provide a fantastic window into processes that are beyond the reach of static (T=0K) calculations. In this paper, the challenges of constant-temperature ab initio MD simulations are discussed and examples given: the formation of H2*, the diffusion of small self-interstitial clusters, the restless interstitial H2 molecule, and the dynamic calculation of vibrational frequencies from the velocity-velocity autocorrelation function. The results are obtained using methods based on Sankey's 'ab initio tight-binding' approach, with atomic-like basis sets rather than plane waves.
Original language | English |
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Pages (from-to) | 1-7 |
Number of pages | 7 |
Journal | Physica B: Condensed Matter |
Volume | 308-310 |
DOIs | |
State | Published - Dec 2001 |
Keywords
- Hydrogen
- Molecular-dynamics
- Self-interstitials
- Silicon