Free-Energy Perturbation

• Each stage of a FEP method should be used only for “encompassing systems”

  • important configurations of one system form a subset of the configurations that are important to the other
  • staging may be needed to bring this about

• The superset will have a higher entropy

  • use “H” and “L” to distinguish high- and low-entropy systems

• Remember hard-sphere with test particle

  • Every configuration of non-overlap isimportant to the N+1 particle (L) system
  • But every one of these configurations is of uniform importance in the N-particle(H) system

Previous slide

Next slide

Back to first slide

View graphic version