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Equilibrium properties of a hysteresis dimer molecule from MD simulations using two-body potentials

Christopher G. Jesudason
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Abstract

Recent experiments indicate that electromagnetic hysteresis behavior can be exhibited at the molecular level.A MD simulation using 2-body potentials and switches to form and break bonds is implemented to determine whether chemical reaction pathways might also exhibit analogous behavior whilst preserving conventional thermodynamical outcomes. The results of various common thermodynamical and kinetic properties are presented, where no unusual thermodynamics is observed. A potential switching technique circumvents the problem of computer intensive three-body calculations which makes this model particularly suitable for numerical investigations in both equilibrium and nonequilibrium states . A new algorithm for the conservation of energy and momentum is incorporated. The thermodynamical parameters determined include the standard free energy, enthalpy and entropy, the activity coefficient ratios, the equilibrium constant and the many energy distribution functions of the molecule, all of which are compared to the Maxwell distribution function. The results do not support recent MNET theories nor the principle of local equilibrium as fundamental principles. A non-cosine dependent rotational variable is suggested for first order relaxation processes. A revision of time reversibility concepts is suggested.

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Christopher G. Jesudason. 2005-09-13. Equilibrium properties of a hysteresis dimer molecule from MD simulations using two-body potentials. https://arxiv.org/abs/physics/0509093

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