Nonequilibrium thermodynamics of interfaces using classical density functional theory.

A vapor-liquid interface introduces resistivities for mass and heat transfer. These resistivities have recently been determined from molecular simulations, as well as theoretically using the van der Waals square gradient model. This model, however, does not allow for direct quantitative comparison to experiment or results from molecular simulations. The classical density functional theory is used here in order to determine the equilibrium profiles of vapor-liquid interfaces. Equilibrium profiles are sufficient in the framework of nonequilibrium thermodynamics for determining the interfacial resistivities. The interfacial resistivities for heat transfer, for mass transfer, and for the coupling of heat and mass transfer can all be related to only one local thermal resistivity. This is done with integral relations for the interfacial resistivities. All interfacial resistivities can be consistently described in their temperature behavior with good accuracy.