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Abstract / Description of output
Molecular dynamics typically incorporates a stochasticdynamical device, a “thermostat,” in order to drive the system to the Gibbs (canonical) distribution at a prescribed temperature. When molecular dynamics is used to compute timedependent properties, such as autocorrelation functions or diffusion constants, at a given temperature, there is a conflict between the need for the thermostat to perturb the time evolution of the system as little as possible and the need to establish equilibrium rapidly. In this article we define a quantity called the “efficiency” of a thermostat which relates the perturbation introduced by the thermostat to the rate of convergence of average kinetic energy to its equilibrium value. We show how to estimate this quantity analytically, carrying out the analysis for several thermostats, including the NoséHooverLangevin thermostat due to Samoletov et al. (J. Stat. Phys. 128:1321–1336, 2007) and a generalization of the “stochastic velocity rescaling” method suggested by Bussi et al. (J. Chem. Phys. 126:014101, 2007). We find efficiency improvements (proportional to the number of degrees of freedom) for the new schemes compared to Langevin Dynamics. Numerical experiments are presented which precisely confirm our theoretical estimates.
Original language  English 

Pages (fromto)  921942 
Journal  Journal of Statistical Physics 
Volume  143 
Issue number  5 
Early online date  11 May 2011 
DOIs  
Publication status  Published  2011 
Keywords / Materials (for Nontextual outputs)
 molecular dynamics
 stochastic thermostats
 langevin dynamics
 thermodynamic averages
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Dive into the research topics of 'Comparing the Efficiencies of Stochastic Isothermal Molecular Dynamics Methods'. Together they form a unique fingerprint.Projects
 1 Finished

Science and Innovation: Numerical Algorithms and Intelligent Software for the Evolving HPC Platform
1/08/09 → 31/07/14
Project: Research