An equation for this quantity can by derived from the Barker-Henderson perturbation model.
An equation for this quantity can by derived from the Barker-Henderson perturbation model. Relating the first derivative of it to the deformation gradient gives the Piola-Kirchoff stress, while the Gibbs-Bogoliubov Inequality relates it to the expectation value of the Hamiltonian. Its average per particle is reduced proportional to density when the attractive force is added to the van der Waals equation. The partial derivative of this quantity with respect to particle number is the chemical potential, when under constant temperature and volume. Equal to the internal energy minus temperature times entropy, or U-TS, FTP, name this quantity which can be denoted A or F, a type of free energy that isn't Gibbs.
An equation for this quantity can by derived from the Barker-Henderson perturbation model.
{Helmholtz free energy}