NVU dynamics. I. Geodesic motion on the constant-potential-energy hypersurface

Details NVU dynamics. I. Geodesic motion on the constant-potential-energy hypersurface NVU dynamics. I. Geodesic motion on the constant-potential-energy hypersurface

2010-12-15

arxiv.org/abs/1012.3447v2

J. Chem. Phys. 135, 104101 (2011)

Physics

Condensed Matter

Soft Condensed Matter

Scientific paper

An algorithm is derived for computer simulation of geodesics on the constant potential-energy hypersurface of a system of N classical particles. First, a basic time-reversible geodesic algorithm is derived by discretizing the geodesic stationarity condition and implementing the constant potential energy constraint via standard Lagrangian multipliers. The basic NVU algorithm is tested by single-precision computer simulations of the Lennard-Jones liquid. Excellent numerical stability is obtained if the force cutoff is smoothed and the two initial configurations have identical potential energy within machine precision. Nevertheless, just as for NVE algorithms, stabilizers are needed for very long runs in order to compensate for the accumulation of numerical errors that eventually lead to "entropic drift" of the potential energy towards higher values. A modification of the basic NVU algorithm is introduced that ensures potential-energy and step-length conservation; center-of-mass drift is also eliminated. Analytical arguments confirmed by simulations demonstrate that the modified NVU algorithm is absolutely stable. Finally, simulations show that the NVU algorithm and the standard leap-frog NVE algorithm have identical radial distribution functions for the Lennard-Jones liquid.

Affiliated with

Also associated with

No associations

Rating

NVU dynamics. I. Geodesic motion on the constant-potential-energy hypersurface does not yet have a rating. At this time, there are no reviews or comments for this scientific paper.

If you have personal experience with NVU dynamics. I. Geodesic motion on the constant-potential-energy hypersurface, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and NVU dynamics. I. Geodesic motion on the constant-potential-energy hypersurface will most certainly appreciate the feedback.

Rate now

Comments { 0 }

Profile ID: LFWR-SCP-O-217957