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Symplectic algorithm for constant-pressure molecular dynamics using a Nose-Poincare thermostat

Jess B. Sturgeon·Brian B. Laird
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Abstract

We present a new algorithm for isothermal-isobaric molecular-dynamics simulation. The method uses an extended Hamiltonian with an Andersen piston combined with the Nos'e-Poincar'e thermostat, recently developed by Bond, Leimkuhler and Laird [J. Comp. Phys., 151, (1999)]. This Nos'e-Poincar'e-Andersen (NPA) formulation has advantages over the Nos'e-Hoover-Andersen approach in that the NPA is Hamiltonian and can take advantage of symplectic integration schemes, which lead to enhanced stability for long-time simulations. The equations of motion are integrated using a Generalized Leapfrog Algorithm and the method is easy to implement, symplectic, explicit and time reversible. To demonstrate the stability of the method we show results for test simulations using a model for aluminum.

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Jess B. Sturgeon, Brian B. Laird. 1999-03-04. Symplectic algorithm for constant-pressure molecular dynamics using a Nose-Poincare thermostat. https://doi.org/10.1063/1.480502

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