Influence of step errors (truncation errors) on results of molecular dynamics simulations

• Autorzy: Litniewski M.
• Konferencja: 8th Workshop of the Polish Society of Computer Simulation (30.08-1.09.2001, Gdańsk-Sobieszewo, Poland)
• Języki publikacji: EN

Abstrakty

EN

Step errors (local errors, called also truncation errors) of the algorithms used in molecular dynamics simulations may result in non-physical correlations between particle velocities, as well as in errors of thermodynamic properties of simulated systems (energy, pressure). The simulations of the Lennard-Jones liquid showed, that the influence is especially high for the Verlet velocity algorithm. Beeman's technique decreases the correlations between the velocities, but at high densities the values of the errors of general averages are close to that of the Verlet method. The influence of step errors can be decreased by about two orders of magnitude by applying the Cowell-Numerov 4-th order implicit method (equivalent to the Gear 4-th order method treated as an implicit one). The method is very stable (more stable than the Verlet one), and can be highly optimized by restricting iteration to the closest neighbors of a given particle. As a result, the method becomes more efficient than the higher order explicit symplectic methods.

Słowa kluczowe

EN

error; molecular dynamics; symplectic; Verlet; Beeman; Cowell-Numerov

• Wydawca: Politechnika Gdańska
• Czasopismo: TASK Quarterly : scientific bulletin of Academic Computer Centre in Gdansk
• Rocznik: 2002
• Tom: Vol. 6, No 3
• Strony: 461--468
• Opis fizyczny: Bibliogr. 12 poz., rys., tab.

Twórcy

autor

Litniewski M.

• Institute of Physical Chemistry, Polish Academy of Sciences, Kasprzaka 44/52, 01-224 Warsaw, Poland

Bibliografia

• [1] Verlet L 1967 Phys. Rev. 159 98
• [2] Allen M P and Tildesley D J 1987 Computer Simulations of Liquids, Clarendon Press, Oxford
• [3] Berendsen J C and van Gunsteren W F 1986 Proc. Enrico Fermi Summer School (Ciccotti G and Hoover W G , Eds.), Varenna 1985, North Holland, New York
• [4] Isbister D J, Searles D J and Evans D J 1997 Physica A240 105
• [5] MacGowan D and Heyes D M 1988 Mol. Simul. 1 277
• [6] Beeman D 1976 J. Comput. Phys. 20 130
• [7] Rodger P M 1989 Mol. Simul. 3 263
• [8] Dahlquist G and Bjorck A 1974 Numerical Methods, Prentice-Hall, New York
• [9] Skeel R D, Zhang G and Schlick T 1997 SIAM J. Sci. Comput. 18 203
• [10] The results of this section, except for those concerning Figure 1, will be published in Molecular Simulation
• [11] Okunbor D I and Skeel R D 1992 J. Comput. Chem. 15 72
• [12] Gray S K, Noid D W and Sumpter B G 1994 J. Chem. Phys. 101 4062