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تسجيل مستخدم جديدChemical Potential Calculations In Dense Liquids Using Metadynamics
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The calculation of chemical potential has traditionally been a challenge in atomistic simulations. One of the most used approaches is Widoms insertion method in which the chemical potential is calculated by periodically attempting to insert an extra particle in the system. In dense systems this method fails since the insertion probability is very low. In this paper we show that in a homogeneous fluid the insertion probability can be increased using metadynamics. We test our method on a supercooled high density binary Lennard-Jones fluid. We find that we can obtain efficiently converged results even when Widoms method fails.
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The numerical computation of chemical potential in dense, non-homogeneous fluids is a key problem in the study of confined fluids thermodynamics. To this day several methods have been proposed, however there is still need for a robust technique, capa
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