Category:Advanced molecular-dynamics sampling

In a molecular-dynamics (MD) calculation, we are often interested in rare events or specific transitions. Advanced molecular-dynamics sampling helps to capture these during an MD run within a feasible simulation time.

Theory

Interface pinning

In interface pinning two different phases of the same system are simulated in a single simulation box. The goal of this method is to look for the right conditions where both phases would coexist, which corresponds to a phase transition point. Above a transition point the whole system would quickly turn into one phase and below the point into the other phase. With this the transition point could be searched via bi sectioning, but this would involve many calculations. To accelerate the search for a phase transition point order parameters are used to control composition and the force that would drive the system towards equilibrium is used to estimate the phase transition point.

Interface pinning is usually used to determine melting points (solid-liquid interface).

• Interface pinning calculations.

• Biased molecular dynamics: Biased molecular dynamics.
• Metadynamics: Metadynamics.
• Constrained molecular dynamics: Constrained molecular dynamics.
• Blue moon ensemble: Blue moon ensemble.
• Slow-growth approach: Slow-growth approach.

How to

• Interface pinning: Interface pinning calculations.
• Constrained molecular dynamics: Constrained molecular dynamics.
• Metadynamics: Metadynamics.
• Biased molecular dynamics: Biased molecular dynamics.
• Slow-growth approach: Slow-growth approach.
• Thermodynamic integration: Thermodynamic integration

References