Computing the absolute Gibbs free energy in atomistic simulations: Applications to defects in solids

  title={Computing the absolute Gibbs free energy in atomistic simulations: Applications to defects in solids},
  author={Bingqing Cheng and Michele Ceriotti},
  journal={Physical Review B},
The Gibbs free energy is the fundamental thermodynamic potential underlying the relative stability of different states of matter under constant-pressure conditions. However, computing this quantity from atomic-scale simulations is far from trivial. As a consequence, all too often the potential energy of the system is used as a proxy, overlooking entropic and anharmonic effects. Here we discuss a combination of different thermodynamic integration routes to obtain the absolute Gibbs free energy… Expand

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