Algorithms for Real Variable Nose-Andersen Constant-Temperature- Constant-Pressure Molecular Dynamics

摘要

An iterative velocity-Verlet, a non-iterative velocity-Verlet and astraightforward centered-difference algorithm are developed for the solution of the Nose-Andersen constant-temperature-constant pressure molecular dynamics equations in real variables. The performances of the algorithms are tested using a Lennard-Jones argon system. Both velocity-Verlet algorithms give a regular behavior whereas the straightforward centered-difference algorithm is found to be unstable. The non-iterative velocity-Verlet algorithm is found to be more accurate than the iterative one. On the other hand, the non-iterative algorithm has a more complex structure than the iterative one.