Statistical Ensembles

Detailed Description

Statistical mechanical ensembles for specific macro-variables.

The classes EnergyEnsemble, BoundaryEnsemble, and SpeciesEnsemble represent statistical ensembles for fluctuations of energy, boundary volume or shape, and number of molecules of a single species, respectively. Each ensemble has a type, which specifies whether the variable has a constant value or if it has a Boltzman-like weight, and stores whatever parameters are needed to describe a Boltzmann ensemble.

The type of a EnergyEnsemble can be "adiabatic" or "isothermal", and a value of temperature is stored if the type is isothermal.

A BoundaryEnsemble can be rigid or isobaric, and stores a pressure value if the type is isobaric.

A Species ensemble can be "closed" or "grand", and stores a value for the chemical potential of a single species if it is grand.

We envision generalizing the BoundaryEnsemble to allow for constant stress ensembles, and may generalize some or all of the ensembles to allow for non-Boltzmann statistical ensembles.

Classes
class	Simp::BoundaryEnsemble
	Statistical ensemble for changes in the periodic unit cell size. More...
class	Simp::EnergyEnsemble
	A statistical ensemble for energy. More...
class	Simp::SpeciesEnsemble
	An ensemble for the number of molecules of one Species. More...