Equations of state

In order to calculate adsorbate properties such as molar mass, vapour pressure or surface tension, pyGAPS makes use of CoolProp or REFPROP. This thermodynamic backend allows for the calculation of multiple fluid state variables.

Note

Not all adsorbates have a thermodynamic backend known to CoolProp. See here for the list of fluids. If not available, the user can provide their own static values for required properties like so.

CoolProp has the ability to use either the open source HEOS or the proprietary REFPROP backend. pyGAPS defaults to using the HEOS backend, but it the user has REFPROP installed and configured on their computer, they can enable it by using the switching function:

pygaps.backend_use_refprop()

To go back to the standard CoolProp backend, use:

pygaps.backend_use_coolprop()

Warning

If REFPROP is not previously installed and configured on the user's computer, calculations will fail.