Modeling alkaline liquid metal (Na) evaporating thin films using both retarded dispersion and electronic force components

A new thin-film evaporation model is presented that captures the unsimplified dispersion force along with an electronic disjoining pressure component that is unique to liquid metals. The resulting nonlinear fourth-order ordinary differential equation (ODE) is solved using implicit orthogonal collocation along with the Levenberg-Marquardt method. The electronic component of the disjoining pressure should be considered when modeling liquid metal extended meniscus evaporation for a wide range of work function boundary values, which represent physical properties of different liquid metals. For liquid sodium, as an example test material, variation in the work function produces order-of-magnitude differences in the film thickness and evaporation profile.